For example, the control unit can control the water flow using a three-port solenoid valve as illustrated in FIGS. In other embodiments, only a magnetic proximity switch or a manual tactile push button switch may be included. The signal can be communicated to the control unit through a wireless connection , as illustrated in FIG.
As can be understood, the tactile push button switch is activated when manually depressed. In contrast, the magnetic proximity switch is activated when a magnet such as the magnet in a container e.
The reed switch is closed by the magnet to actuate the sensor a and the Hall Effect switch produces a voltage change in response to the presence of the magnetic field. Power for the sensor a can be provided by an internal battery, a wired power connection, or other appropriate power supply.
The magnetic proximity switch is activated when a magnet such as the magnet in a container e. The signal can be communicated to the control unit through a wireless connection FIG.
Power for the sensor b can be provided by an internal battery, a wired power connection, or other appropriate power supply. The passive IR proximity switch includes a solid state device that is activated when an object such as a container e. No specific material or other communication device is needed to actuate the passive IR proximity switch.
The sensor c can also include a manual tactile push button switch As previously discussed, the tactile push button switch is activated when manually depressed. Power for the sensor c can be provided by an internal battery, a wired power connection, or other appropriate power supply. While the example of FIG. The RFID switch includes a solid state device that is activated when an object such as a container e.
The sensor d can also include a manual tactile push button switch Power for the sensor d can be provided by an internal battery, a wired power connection, or other appropriate power supply. The photoelectric sensing beam switch includes a solid state device that projects a sensing beam of light towards a photoelectric sensor.
The photoelectric sensing beam switch is activated when an object such as a container e. No specific material or other communication device is needed to actuate the photoelectric sensing beam switch. The sensor e can also include a manual tactile push button switch Power for the sensor e can be provided by an internal battery, a wired power connection, or other appropriate power supply.
The voice sensing switch is activated when a voice, word or phrase is recognized by processing circuitry in the sensor f. The sensor f can also include a manual tactile push button switch not shown in FIG.
Power for the sensor f can be provided by an internal battery, a wired power connection, or other appropriate power supply. The capacitive proximity switch includes a solid state device that senses changes in capacitance when object approach the sensor g. The capacitive proximity switch is activated when an object such as a container e. The signal can be communicated to the control unit through a wireless connection or via a wired connection , as illustrated in FIG. Power for the sensor g can be provided by an internal battery, a wired power connection, or other appropriate power supply.
Other types of capacitive touch sensors can also be utilized by the smart water filter system The capacitive touch sensor h includes a solid state device that senses changes in capacitance when the faucet is touched. The capacitive touch sensor h is activated when a sufficient change in the capacitance is sensed.
In some implementations, a defined sequence or pattern of touches can be used to actuate the capacitive touch sensor h. Power for the sensor h can be provided by an internal battery, a wired power connection, or other appropriate power supply. For example, the capacitive touch sensor h can be coupled to the faucet and positioned on the counter between the faucet and a back splash behind the faucet In some embodiments, sensors can be integrated in the faucet In some implementations, a defined sequence or pattern of breaks can be used to actuate the sensor i.
Power for the sensor i can be provided by an internal battery, a wired power connection, or other appropriate power supply. The passive IR proximity switch is activated when an object such as a container e.
In some implementations, a defined sequence or pattern of movements through the IR sensing field can be used to actuate the sensor j.
Power for the sensor j can be provided by an internal battery, a wired power connection, or other appropriate power supply. The touch screen sensor k can be activated by selecting the appropriate option through the touch screen. Power for the sensor k can be provided by an internal battery, a wired power connection, or other appropriate power supply. In some embodiments, patterns in water flow through the faucet can be monitored to identify when the smart water filtering system should be activated.
The flow sensor can be used to monitor the variations in water flow through the cold water line for identifiable patterns that can be used to initiate operation of the smart water filter system For example, when water flow is first established at or above a first defined level e. The control unit can learn the amount of water flow that corresponds to full flow through the faucet during the initial installation and setup of the smart water filter system The control unit may send a signal to a sensor above the counter to provide an indication to the user that the filtering or other function has been initiated.
For example, the touch screen sensor k of FIG. The smart water filter system or solenoid valve can be deactivated when the water flow through the cold water line is subsequently shut off or when the water flow is subsequently increased to or above the first defined level or to full flow. For example, the control unit can monitor usage of, e. The user interface can be integrated into the control unit or may be remotely located and communicatively coupled to the control unit through the RF transceiver FIG.
The RF transceiver can allow access to the Internet through a local network e. Access to the Internet can also allow the smart water filter system to display to the user notifications from the equipment supplier or other entities such as, e. Condition of replaceable components e. In some cases, replacement components e.
For instance, indications can be provided for the amount of water consumed over a given period of time. While the discussion makes reference to smart water system , the operation is equally applicable to smart water filter systems of FIGS. Beginning with , the smart water filter system waits for initiation of water flow through the water supply line e. In some embodiments, the smart water filter system is energized or in a sleep mode and monitoring on a periodic basis for water flow through one or more sensors as previously discussed.
When flow is sensed by the control unit e. When in a sleep mode, the smart water filter system can wake up and restore the system for normal operation in In other embodiments, the smart water filter system may be shut down with an idle generator in the water supply line. When the generator begins producing power indicating that water flow has started , the smart water filter system starts up for normal operation in The status of the filter bank e. For example, the filters may be designed for use for a predefined period of time or amount of water flow through the filter.
If the filter condition is not acceptable at , then an indication can be provided in In some cases, an indication may be transmitted by the control unit to a remotely located or collocated computer, laptop, tablet, smart phone through a local network or connection, or through the Internet.
The smart water filter system then begins checking for a filtered water request from a sensor in If the filter condition is acceptable at , the smart water filter system then begins checking for the filtered water request in If a filtered water request is not received from a sensor by the control unit within a predefined time period at , then the voltage level or condition of the battery used by the smart water filter system can be checked in If the voltage is acceptable, then the flow returns to , where the smart water filter system continues to check for a filtered water request.
If the voltage level of the battery is not acceptable, then the smart water filter system may proceed to and turn off or enter a sleep mode to conserve power. An indication can be provided to the user in to inform them of the reason for shutting down the system. If a filtered water request is received by the control unit at , then one or more solenoids can be energized at to redirect water flow through the filter bank , chiller unit e.
The control unit can also determine from the signal from the sensor whether a specific container or user has been identified and configure the smart water filter system to operate in accordance with the associated set of predefined preferences as previously discussed. A filter timer can be started in to control how long filtered water is provided. At , the smart water filter system determines whether a change in the water flow has been detected e.
If the change in flow satisfies a predefined flow condition, then the one or more solenoids are de-energized at For example, if the water flow stops because the faucet is turned off or if the water flow increases to full flow, then the smart water filter system stops filtering the water by de-energizing the solenoid s.
If no change if flow is detected, then it is determined if the timer has timed out at If the filter timer has expired at , then the one or more solenoids are de-energized at If the filter timer has not expired, then the water flow is again checked at After the solenoid s are de-energized in , the filter status information is updated in The smart water filter system can then be turned off at In some cases, the smart water filter system can enter a sleep mode and continue monitoring for water flow as previously discussed.
It should be emphasized that the above-described embodiments of the present disclosure are merely possible examples of implementations set forth for a clear understanding of the principles of the disclosure.
Many variations and modifications may be made to the above-described embodiment s without departing substantially from the spirit and principles of the disclosure. All such modifications and variations are intended to be included herein within the scope of this disclosure and protected by the following claims. It should be noted that ratios, concentrations, amounts, and other numerical data may be expressed herein in a range format.
It is to be understood that such a range format is used for convenience and brevity, and thus, should be interpreted in a flexible manner to include not only the numerical values explicitly recited as the limits of the range, but also to include all the individual numerical values or sub-ranges encompassed within that range as if each numerical value and sub-range is explicitly recited. Therefore, at least the following is claimed: 1.
A smart water filter system, comprising: a solenoid valve comprising an inlet coupled to a water supply connection and an outlet coupled to a faucet feed connection, the water supply connection configured to connect to a water supply line and the faucet feed connection configured to couple to a faucet via a faucet feed line;. The smart water filter system of claim 1 , further comprising a control unit configured to activate the solenoid valve in response to a first signal.
The smart water filter system of claim 2 , wherein the first signal is provided by a sensor. Cho, S. Yun and vorable hetero-junction interfaces. Moreover, conduction band G. Li, Y. Guo, F. Zhao, C. Nie, H. Li, J. Shi, X. Liu, J.
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Li, B. Saho, D. Chang and H. Wu, ACS Sens. Sun, Phys. B Phys. Matter, , , — Cheng, D. Dong, Q. Ma, W. Yu, X. Yu, 39 X. The following output provides sample configuration guideline for changing the default port-channel load-balance setting to source-destination-ip based. Aside from Layer-2 or Layer-3 EtherChannel mode, similar configuration must be applied on each system in the access-distribution block and WAN edge.
The following additional EtherChannel design and configuration must be taken into consideration for an optimal EtherChannel design:. Enable single EtherChannel between access-layer and distribution system. Enabling more than a single Ether Channel in a collapsed core network design imposes the same limitations as discussed in non-EtherChannel scenario in Figure For optimal load sharing and hashing computation, it is recommended to bundle the number of physical ports in powers of 2 i.
EtherChannel is a logical interface in Cisco Catalyst platform. EtherChannel scalability in collapsed core and distribution must be taken into account. Deploying Core Network Layer This section provides implementation and best practice guidelines for deploying the core-layer in both the main and remote enterprise sites.
Proper design of the core network layer ensures reachability, transparency and availability. This section focuses on building a unicast routing topology. Routing Protocol Enabling routing in the small enterprise network is a simple task. However, the network physical layout must be carefully planned and designed to ensure flexible, stable and efficient routing. Developing a hierarchical network addressing scheme enables a stable, efficient and scalable design. It is recommended to deploy a single choice of routing protocol across the network infrastructure.
This solution guide does not recommended any particular IGP to deploy in the small enterprise network architecture as it significantly varies based on different network infrastructure. However it will provide some key points to be considered when selecting unicast routing protocol. Hierarchical routing domainRouting protocols must be designed in a hierarchical model that allows network to scale and operate with greater stability.
Building routing boundaries and summarizing the network addresses minimizes topology size and synchronization procedure, which improves the overall network resource utilization and reconvergence. Efficient address allocationHierarchical addressing enables efficient use of address space, since groups are contiguous.
Improves routing efficiencyUsing contiguous ip addresses enables efficient route summarization. Route summarization simplifies the routing database, and computations during topology changes. This reduces the network bandwidth used by the routing protocol, and improves routing protocol performance by reducing network convergence time.
Improves system performanceHierarchical, contiguous ip addressing reduces router memory usage by eliminating dis-contiguous and non-summarized route entries. It saves on CPU cycles needed to compute the routing database during topology changes.
This contributes to a more stable routing network, and simplifies the task of network operations and management. While OSPF is capable of greater scale, it is also more complex, and hence more difficult to configure, operate and manage.
The Small Enterprise Design Profile is designed and validated using EIGRP, since it is a stable, high performance, efficient protocol, which is simple to implement and manage. Built-in mechanic to prevent routing loop in network. All routers considered in backbone.
Non-backbone or OSPF area is divided in multiple routers in non-transit path can be deployed in Stub role. Backbone area maintains complete summarized network topology; non-backbone area can be transit or non-transit OSPF routers. Both routing protocol offers rapid network recovery during link failure. Yes Flexibility to manual summarized on any routing node.
Support equal and un-equal cost load balancing Cisco proprietary Yes. IETF standard. Each remote site is connected to the main site over the WAN infrastructure. The main site network includes the Internet gateway and provides access to the central data-center. Since main and remote sites use the collapsed core design, the routing configuration of the core routers is the same.
The following is a sample configuration to enable EIGRP routing process at the edge of the main site collapsed core network. EIGRP is enabled in the remote sites network with the same configuration: cr config interface Loopback0 cr config-if ip address This behavior needs to be modified to ensure a secure, efficient and stable routing design:.
EIGRP route processing should only be enabled on interfaces where trusted network devices are connected. All other interfaces can be suppressed in passive mode. The following configuration shows how to automatically disable EIGRP processing on all the Layer-3 interfaces and only enable on the trusted interface.
This design principle must be applied on each EIGRP router, including distribution and core routers: cr config router eigrp cr config-router network Or an attacker could establish a fake EIGRP adjacency and advertise a best metric default-route into the network to black hole and compromise all critical traffic. This provides a secure method of transmitting and receiving routing information between devices in the network.
System StabilityAs mentioned in Table 8, EIGRP allows network administrator to summarize multiple individual and contiguous networks into a single summarized network before advertising to neighbors. Route summarization improves performance, stability, and convergence times, and it makes the network easier to manage operate and troubleshoot. EIGRP provides the flexibility to summarize at any point in the network.
Proper design requires determining which routers will serve as Aggregators, and advertise summarized network information to peers.
Routers which connect multiple access devices, or connect to the WAN edge should be made Aggregators. Figure provides an example small enterprise network with route aggregator devices identified with the direction of route summarization illustrated. Distribution cr config interface Port-channel1 cr config-if description Connected to crME-1 cr config-if ip summary-address eigrp All the prefixes discovered from a dead neighbor are removed from the routing table.
In the event of a single member-link failure condition, layer 2 will respond more quickly than the routing protocol, and switchover traffic from the impacted link to an alternate member link. EIGRP routing is not impacted by individual link member and no change in the routing table is required. Thus reducing the EIGRP timers will not result in quicker convergence, and may adversely impact system stability.
High availabilityThe Cisco Catalyst R-E and X Stack Wise Plus layer 3 switches support graceful-restart protocol extensions which enables a redundant module or member switch to gracefully assume the active role while maintaining adjacency with neighbors, during a active supervisor failure condition. The backup supervisor requires sufficient time to detect a failure and initiate graceful recovery with neighbors. Implementing aggressive timers may abruptly terminate adjacency and cause network outage before a stateful switch over is accomplished.
This section provides implementation and best practices guidelines the multi-layer design. The deployment and configuration guidelines for the multi-layer access-distribution block are the same for both main and remote site networks. The Small Enterprise Design Profile uses Etherchannel point-to-point logical Layer-2 bundle connection between access-layer and distribution switch which inherently simplifies the STP topology and operation.
In this design, the STP operation is done on a logical port, therefore, it will be assigned automatically in forwarding state. Over the years, the STP protocols have evolved into the following versions:. It is easy to implement, proven in large scale networks that support up to logical ports and greatly improves network restoration time.
Distribution cr config spanning-tree mode rapid-pvst cr show spanning-tree summary inc mode Switch is in rapid-pvst mode. Default STP parameters optimize the network for packet forwarding. Best practice design includes hardening STP parameters in the access and distribution switch to protect against STP misconfiguration, or malicious user by deploying spanning-tree toolkit in the access-distribution block.
Other STP Toolkit Consideration When the access-distribution block multi-layer design is deployed using the recommended best practices, it automatically minimizes the need for deploying the following additional spanning-tree toolkit technologies:. UplinkFastImproves the network convergence time by providing direct access to the root switch link failure. BackBone FastProvides rapid convergence from indirect Layer-2 link failures in a redundant distribution switch configuration.
This is feature is not necessary for the same reason as stated for UplinkFast. A STP loop is created when a blocking port in a redundant topology erroneously transitions to the forwarding state. This usually happens because one of the ports in a physically redundant topology not necessarily the blocking port stopped receiving BPDUs.
Because there is single point-to-point STP forwarding port in this design, enabling Loopguard does not provide any additional benefit. UDLD protocol must be implemented to prevent STP loop that may occur in the network due to network malfunction, mis-wiring, etc. There are three basic ways to assign VLANs within the access-distribution block. Flat Logical Network Design Spanning a single VLAN across multiple access-layer switches is much simpler with a single collapsed core-distribution device versus a design with redundant distribution devices.
ScalabilitySpanning the same VLAN in different access-layer switches will create a large Layer-2 broadcast domain that dynamically discovers and populates MAC address entries for endpoints that may not need to communicate. In a large network, this may become a scalability issue i.
PerformanceIn a large network, spanning a large number of broadcast domains will impact the performance of all network devices in the access-distribution block, because the switch will have to process many more broadcast packets such as ARP. SecurityThe flat muli0layer design widens the fault domain which increases possible attacks to a larger number of users. The number of users is not necessarily due to the number switches spanned and applications during DoS or viruses attack.
Segmented Logical Network Design Best practice design includes identifying meaningful groups within the user community, and assigning a unique VLAN to each group. These groups may be departments, user groups, or any other logical grouping of users. Enabling a unique VLAN for each group will segment the network and build a logical network structure.
All network communication between groups will pass through the routing and forwarding policies defined at the distribution layer. A segmented VLAN design is the solution to the challenges described in the flat network design.
VLAN segmentation improves the scalability, performance, and security of the network. Hybrid Logical Network Design The segmented logical network design improves scalability, performance and security, and addresses the challenges of a flat network design. In real world deployments, there is usually a need for some users or applications to communicate with all users eg system administrator.
The hybrid network design is the segmented design, with the addition of a exceptional VLAN which spans the entire access-distribution block. Cisco recommends the segmented VLAN network design and optionally hybrid network for centralized users or applications that requires distributed function across the access-layer network. Following are the sample VLAN configuration steps in the access and the distribution layer switches.
Cisco's VTP simplifies administration in a switched network. VTP can be configured in three modes: server, client, and transparent. Set the VTP domain name and change the mode to the transparent mode as follows: cr config vtp domain campus cr config vtp mode transparent cr config vlan 10 cr config-vlan name cr config-vlan vlan cr config-vlan name cr config-vlan vlan cr config-vlan name.
Access Set VTP domain name and change the mode to the transparent mode as follows: cr config vtp domain campus cr config vtp mode transparent cr config vlan 10 cr config-vlan name crSales-Dept. The network connection between Distribution and Access device is a trunk. The native VLAN remains active on all access switches layer 2 ports. It is recommended to implement trunk encapsulation in static mode instead of negotiating mode, to improve the rapid link bring-up performance.
Enabling the Layer-2 trunk on a port-channel, automatically enables communication for all of the active VLANs between the access and distribution. This means an access-switch which has implemented, for example, VLANs 10 to 15, will receive flood traffic destined for VLANs 20 to 25, which are implemented on another access switch.
In a large network, it is important to limit traffic on Layer-2 trunk ports to only the assigned VLANS, to ensure efficient and secure network performance. Allowing only assigned VLANs on a trunk port automatically filters rest.
The default native VLAN must be properly configured to avoid several security risksAttack, worm and virus or data theft. Any malicious traffic originated in VLAN 1 will span across the access-layer network. For example, configure VLAN. Then change the default native VLAN setting in both the switches.
Thereafter, VLAN must not be used anywhere for any purpose in the same access-distribution block. When the following configurations are applied on port-channel interface i.
Distribution cr config vlan cr config-vlan name Admin-Hopping-VLAN cr config interface Port-channel 11 cr config-if description Connected to cr cr config-if switchport cr config-if switchport mode trunk cr config-if switchport trunk allowed vlan , cr config-if switchport trunk native vlan Vlans allowed on trunk , Vlans allowed and active in management domain , Vlans in spanning tree forwarding state and not pruned , Access-switch cr config vlan cr config-vlan name Admin-Hopping-VLAN cr config interface Port-channel 1 cr config-if description Connected to cr cr config-if switchport cr config-if switchport mode trunk cr config-if switchport trunk allowed vlan , cr config-if switchport trunk native vlan At Layer 1, auto-negotiation takes care of physical signaling and fault detection.
UDLD performs tasks that auto-negotiation cannot perform, such as detecting the identity of neighbors and shutting down. When both auto-negotiation and UDLD are enabled, Layer 1 and Layer 2 detection works together to prevent physical and logical unidirectional connections and the malfunctioning of other protocols. Copper media ports use Ethernet link pulse as a link monitoring tool and are not susceptible to unidirectional link problems.
When such physical connection errors occur, it can cause loops or traffic black holes. UDLD operates in one of two modes:. Normal modeIf bidirectional UDLD protocol state information times out; it is assumed there is no-fault in the network, and no further action is taken.
The port state for UDLD is marked as undetermined. The port behaves according to its STP state. Aggressive modeIf bidirectional UDLD protocol state information times out, UDLD will attempt to reestablish the state of the port, if it detects the link on the port is operational. Failure to reestablish communication with UDLD neighbor will force the port into the err-disable state.
That must be manually recovered by user or the switch can be configured for auto recovery within specified interval of time. Deploying Routed-Access Network This section provides implementation and best practices guidelines to deploy routed-access in the access-distribution block.
The routed access design moves the boundary between Layer 2 and Layer 3 from the distribution layer to the access layer as seen in Figure Routing in the access-layer simplifies configuration, optimizes distribution performance, and improves end-to-end troubleshooting tools. Implementing routing in the access-layer replaces Layer-2 trunk configuration with single point-to-point Layer-3 interface in distribution layer. Placing Layer-3 function one tier down on access-switches, changes the multilayer network topology and forwarding path.
Implementing Layer-3 function in the access-switch does not require a physical or logical link reconfiguration; the same EtherChannel in access-distribution block can be used.
At the network edge, Layer-3 access-switches provides an IP gateway and become the Layer-2 demarcation point to locally connected endpoints that could be logically segmented into multiple VLANs. Following are the benefits of implementing routed-access in the access-distribution block:. As a best practice, STP toolkit must be hardened at the access-layer. Improves Layer-3 uplink bandwidth efficiency by suppressing Layer-2 broadcasts at the access edge port.
Improves performance by reducing resource utilization in collapsed core-distribution layer. In a large multilayer network, the aggregation layer may consume more CPU cycles due to the large number of MAC and ARP discovery and processing and storing required for each end-station. Routed-access reduces the load of this Layer-2 processing and storage in the distribution layer, by moving the load to layer-3 access-switches.
Figure illustrates where Layer-2 and Layer-3 forwarding entry processing and storage takes place when access-distribution block is implemented as multi-layer versus routed-access network.
While the routed access design is appropriate for many small enterprise networks it is not suitable for all environments. Routed access does not allow a VLAN to span multiple access switches. All the deployment and configuration guidelines in this section are the same for deploying in the main or remote site network.
Following is the example configuration to enable basic EIGRP routing in the distribution layer and in the access layer:. Distribution cr config interface Port-channel13 cr config-if description Connected to crr-1 cr config-if no switchport cr config-if ip address Access crr-1 config interface Loopback0 crr-1 config-if ip address Building a single routing domain enables complete network visibility and reach ability between all of the elements within the network.
The access switch will build a forwarding topology pointing to same distribution switch as a single Layer-3 next-hop. Since the distribution switch provides a gateway function to the access switch, the routing design can be optimized with the following two techniques to improve performance and network convergence in the access-distribution block:.
Announcing itself as a non-transit stub Layer-3 router is one way to notify the distribution router that it should not include the Layer-3 access switch in the EIGRP topology recomputation process. This optimized recomputation process will prevent unnecessary EIGRP network queries, which reduces network traffic, and simplifies the route computation.
EIGRP stub router in Layer-3 access-switch can announce routes to a distribution-layer router with great flexibility. EIGRP stub router can be deployed to announce routes dynamically discovered or statically configured. Best practice design is to deploy EIGRP stub router to announce locally learned routes to aggregation layer. The Distribution router must be configured to advertise summarized routes that do not compromise end-to-end reach ability, and help access switches maintain minimal routing information.
In a network with a well designed IP addressing scheme, the aggregation system can advertise summarized routes in a classless address configuration, that reduce individual network advertisements, improve network scalability and network convergence.
The distribution router must have full network topology information to ensure efficient reachability paths. Therefore, it is recommended to summarize at the distribution router, and not summarize at the access-layer. Route summarization must be implemented on the distribution layer of main and each remote site network. This includes devices such as the WAN aggregation in the main site. The distribution router must advertise the following summarized network information to Layer 3 access-switch:.
Local NetworkDistribution router can be implemented in hybrid access-distribution configuration that interconnects several multi-layer or routed-access enabled access-layer switches.
Independent of route origination source connected or dynamic route and network size within the access-distribution block, the distribution router in main and remote site network must advertise a single, concise and summarized Layer 3 network to each Layer 3 access-switch and to core devices. Remote NetworkSummarized network will be propagated dynamically across the network.
Single summarization of all remote networks may be advertised to local Layer 3 access-switches, since it improves bandwidth efficiency. During a network outage, Layer 3 access-switch may drop traffic at the network edge instead of transmitting it to the distribution router to black hole traffic. Default NetworkWhen Layer 3 access-switch receives un-known destination traffic from the edge that does not match any of the above mentioned summarized networks, then it is sent to the distribution router to make a forwarding decision.
The distribution router performs a forwarding table lookup and may forward to appropriate path or black hole the traffic. In a typical small enterprise network environment, a default route is announced by an Internet edge system, to forward all internet traffic. Distribution router must propagate this default route to the Layer 3 access-switch.
Figure illustrates a summarized EIGRP network advertisement, by route aggregation system, that provides end-to-end internal and external network reachability. Following is configuration example to deploy summarized and filtered Layer-3 network information to Layer-3 access-switch. Distribution interface Port-channel13 description Connected to crr-1 dampening ip address Access crr-1 show ip route eigrp The two challenges, system efficiency, and network security also apply equally to the routed access design, and the same solution is applied:.
EIGRP routing process should only be enabled on interfaces where trusted enterprise devices are connected.
Following is the example configuration on Layer-3 access-switch that advertises networks enabled on SVI interfaces; however, keeps them in passive mode and explicitly allows EIGRP function on uplink port-channel to distribution router. Same configuration principle must be applied on each EIGRP router including distribution and core routers: crr-1 config router eigrp crr-1 config-router network It is highly recommended to retain default EIGRP hello and hold timers on distribution and Layer 3 access-switch and rely on EtherChannel and SSO-based recovery mechanisms, that offers sub-second network convergence, during individual link or supervisor failure scenarios.
UnicastOne source sends a message to one destination BroadcastOne source sends a message to all destinations MulticastOne source sends a message to a subset of destinations. IP multicast allows a source to transmit a message as a group transmission to a subset of hosts on the network. Many collaboration applications, such as video conferencing, distance learning, software distribution, utilize multicast techniques. IP multicast improves network bandwidth utilization, by reducing un necessary duplicate traffic.
Multicast improves efficiency by reducing data processing on the source server, and sending a single flow into the network. Multicast packets are replicated in the network where paths diverge, by Protocol Independent Multicast PIM -enabled routers, and other supporting multicast protocols.
A range of class D address space is assigned for IP multicast applications. All multicast group addresses fall in the range of In IP multicast packets, the destination IP address is in the multicast group range, while the source IP address is always in the unicast address range. The multicast IP address space is further divided into several pools for well-known multicast network protocols, and inter-domain multicast communications as shown in Table Commonly deployed in enterprise and other organization.
Multicast Routing Design Each device between a multicast source and receiver must enable dynamic multicast. The technique for creating a multicast forwarding table is different than unicast routing and switching techniques. Multicast Routing Protocol IP multicast delivers source traffic to multiple receivers using the least amount of network resources, without placing additional burden on the source or the receivers. Multicast packet replication in the network is performed by Cisco routers and switches enabled with Protocol Independent Multicast PIM and other multicast routing protocols.
In this network, we further identified key molecules and targets using degrees Table 5. Physcion, emodin, 3- 4-Hydroxyphenyl acrylic acid 4-hydroxyphenethyl ester and meso-dihydroguaiaretic acid were the most important components that regulates the above two pathways. The triangles represent the components, the quadrangles represent the pathways, and the squarenesses represent the targets that can be regulated by the components and are in the pathways. The darker nodes represent higher degrees.
In China, traditional Chinese medicine prescriptions are widely used to treat recurrent UC. The mechanism of these drug combination based on the basic theory of traditional Chinese medicine is often difficult to elucidate due to the complexity of the components.
The holistic view of Chinese medicine has a lot in common with the key ideas of network pharmacology and systems biology. This network-based approach can explain the combination rules and network regulation effects of herbal formulas [ 21 ]. Combined with the bioinformatics research on diseases, we can more clearly define the targets and specific mechanisms of Chinese medicine on the diseases, and identify key active molecules. This is of great significance to the development of natural medicines and the treatment of diseases.
In our study, we successfully identified eight active molecules and two important pathways related to UC through network pharmacology and bioinformatics. Therefore, Caulis Sargentodoxae can improve UC by regulating them. According to Components-Targets-Pathways network, the degrees of physcion, emodin, 3- 4-Hydroxyphenyl acrylic acid 4-hydroxyphenethyl ester and meso-dihydroguaiaretic acid were the highest.
Physcion is an anthraquinone compound commonly found in various plants, and shows anti-cancer properties in a variety of tumors. This indicated that it has good anti-inflammatory ability.
And in our study, it was also identified as the most critical component for the treatment of UC. Emodin is a natural anthraquinone derivative with a wide range of pharmacological properties, including anticancer, liver protection, anti-inflammatory, antioxidant and antibacterial activities [ 28 ]. This is consistent with our computer-based research, and indicates that emodin can regulate PI3K-Akt signaling pathway to exert anti-inflammatory effects.
However, the pharmacological activity of 3- 4-Hydroxyphenyl acrylic acid 4-hydroxyphenethyl ester has not been reported yet, and further experiments are needed. Overall, our results suggested that Caulis Sargentodoxae can treat UC through regulating HIF-1 signaling pathway and PI3K-Akt signaling pathway, but this effect is a synergistic effect of eight active components.
It is necessary to further compare the therapeutic effects of Caulis Sargentodoxae and its different components in animal models, and further evaluate these molecules in terms of safety and higher efficacy.
Analyzing and verifying the effective dose and toxicity of different molecules by using pharmacology and toxicology experiments will also have important significance for clinical applications. The data used to support the findings of the present study are included within the article and the supplementary files.
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Previous Article Next Article. All Issues. Cover Image Cover Image. The cover of this issue of Bioscience Reports volume 41, issue 1 features the crystal structure of aldehyde dehydrogenase AldA from a research article by Zhang et al.
The plant pathogenic microbe Pseudomonas syringae uses AldA for the synthesis of indole acetic acid IAA , a major plant hormone. The x-ray crystal structure of AldA in complex with IAA helps understand how these enzyme recognizes substrate and performs its reaction chemistry. Materials and methods. Data Availability. Competing Interests. Author Contribution. Article Navigation.
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