What's the function of the Cisco module

What's the function of the Cisco light module ?

Cisco module classification and description:

1 Cisco 1 × 9 package optical modules: welding type module, general speed is less than1000m, using SC interface.

2 SFF package, Cisco optical module: welding small package module, general speed is less than 1000m, using LC interface.

3 GBIC package, Cisco optical module: hot pluggable Gigabit interface module, using SC interface.

4 SFP package, Cisco optical module: hot plug small package module, the highest rate of up to 4G, use the LC interface.

5 XENPAK package, Cisco optical module: applications in Gigabit Ethernet, using the SC interface.

The optical module is connected to the module of a photoelectric conversion effect, which transmit the electric signal into optical signal, the optical fiber transmission, the receiving end ofthe optical signals are converted into electric signals. The optoelectronic devices, circuits andoptical interface and other components, optoelectronic devices including the transmitting and receiving two parts.

Cisco 4500 6500 and 7600 are modular design, apart from the main chassis, supervisor engine,linecard, power supplies and modules will be also required for these products. 3Anetwork.comwholesales Cisco 450065007600 Modules, ship to worldwide.

WS-X6748-GE-TX, WS-X6724-SFP the popular cisco module up to 50% off on 3anetwork.com.

Removing SFP and SFP+ Transceiver Modules

Caution 1: The SFP and SFP+ transceiver modules are static sensitive devices. Always use an ESD wrist strap or similar individual grounding device when handling the transceiver modules or coming in contact with modules, I use the Cisco SFP GLC-SX-MMD and SFP-10G-LR most time on the network.

Caution 2: Be careful when removing GLC-GE-100FX SFPs from a WS-C3750G-12S-S switch. The SFP transceiver module temperature might go over 160°F (70°C) and be too hot to touch with bare hands.

If you are removing an SFP or SFP+ transceiver module, follow these steps:

Step 1 Attach an ESD-preventive wrist strap to your wrist and to the ESD ground connector or a bare metal surface on your chassis.

Step 2 Disconnect the network fiber-optic cable or network copper cable from the transceiver module connector. For optical transceiver modules, immediately reinstall the dust plugs in the transceiver module's optical bores and the fiber-optic cable LC connectors.

Tip: For reattachment of fiber-optic cables, note which connector plug is send (TX) and which is receive (RX).

Step 3 Release and remove the transceiver module from the socket connector, as shown in Figure 1 , Figure 2, Figure 3, or

•If the SFP transceiver module has a Mylar tab latch, pull the tab gently in a slightly downward direction until the transceiver disengages from the socket connector, and then pull the SFP transceiver module straight out. Do not twist or pull the Mylar tab because you could detach it from the SFP transceiver module.

Figure 1 Removing an SFP Transceiver Module Equipped with a Mylar Tab

•If the SFP transceiver module has an actuator button latch, gently press the actuator button on the front of the SFP transceiver module until it clicks and the latch mechanism releases the SFP transceiver module from the socket connector. Grasp the actuator button between your thumb and index finger, and carefully pull the SFP transceiver module straight from the module slot.

Figure 2 Removing an SFP Transceiver Module Equipped with an Actuator Button Latch

•If the SFP transceiver module has a bail clasp latch, pull the latch out and down to eject the SFP transceiver module from the socket connector. If the bail clasp latch is obstructed and you cannot use your index finger to open it, use a small, flat-blade screwdriver or other long, narrow instrument to open the bail clasp latch. Grasp the SFP transceiver module between your thumb and index finger, and carefully remove it from the socket.

Figure 3 Removing an SFP Transceiver Module Equipped with a Bail Clasp Latch

•The SFP+ transceiver uses a bail clasp style latch which is slightly different than the bail clasp latch for the SFP transceiver. The SFP+ transceiver bail clasp has a small tab protruding down from the bail clasp handle To release the SFP+ bail clasp, push the small tab up and outwards with your index finger to release the bail clasp. Grasp the SFP+ transceiver between your thumb and index finger and carefully remove the transceiver from the socket.

Figure 4 Removing an SFP+ Transceiver Equipped with a Bail Clasp Latch with Tab

Step 4 Place the removed transceiver module in an antistatic bag or other protective environment.

Installing SFP and SFP+ Transceiver Modules

Installing SFP and SFP+ Transceiver Modules

Required Tools

You will need these tools to install the SFP transceiver module:

1 Wrist strap or other personal grounding device to prevent ESD occurrences.

2 Antistatic mat or antistatic foam to set the transceiver on.

Note: Fiber-optic end-face cleaning tools and inspection equipment. For complete information on inspecting and cleaning fiber-optic connections, see the white-paper document at this URL:

http://www.cisco.com/en/US/tech/tk482/tk876/technologies_white_paper09186a0080254eba.shtml

SFP transceiver modules can have three types of latching devices to secure an SFP transceiver module in a port socket:

•Figure 1 shows an SFP transceiver module with a Mylar tab latch.

•Figure 2 shows an SFP transceiver module with an actuator button latch.

•Figure 3 shows an SFP transceiver module that has a bail clasp latch.

•Figure 4 shows an SFP+ transceiver module that has a bail clasp latch.

Determine which type of latch your SFP transceiver module uses before following the installation and removal procedures.

Caution 1 Do not install or remove the SFP transceiver module with fiber-optic cables still attached to it. Doing so may damage cables, cable connectors, or the optical interfaces and may interfere with the SFP transceiver module latching properly into its socket connector. Disconnect all cables before removing or installing an SFP transceiver module.

Caution 2 The SFP transceiver modules are static sensitive devices. Always use an ESD wrist strap or similar individual grounding device when handling SFP transceiver modules or coming in contact with modules.

Figure 1 SFP Transceiver Module with a Mylar Tab Latch

Figure 2 SFP Transceiver Module with an Actuator Button Latch

Figure 3 SFP Module with a Bail Clasp Latch

Figure 4 SFP+ Module with a Bail Clasp Latch

To install an SFP transceiver module, follow these steps:

Step 1 Attach an ESD-preventive wrist strap to your wrist and to the ESD ground connector or a bare metal surface on your chassis.

Step 2 Remove the SFP transceiver module from its protective packaging.

Note Do not remove the optical bore dust plugs until directed to do so later in the procedure.

Step 3 Check the label on the SFP transceiver module body to verify that you have the correct model for your network.

Step 4 Find the send (TX) and receive (RX) markings that identify the top side of the SFP transceiver module.

Note On some SFP transceiver modules, the TX and RX marking might be replaced by arrowheads pointing from the SFP transceiver module connector (transmit direction or TX) and toward the connector (receive direction or RX).

Step 5 Position the SFP transceiver module in front of the socket opening.

Note Different Cisco devices have different SFP module socket configurations. Your Cisco device could have either a latch-up or a latch-down orientation. Ensure that you are installing the SFP transceiver module in the correct orientation for your Cisco device. For more details, see the hardware installation instructions that came with your Cisco device.

Step 6 Holding it as shown in Figure 5, insert the SFP into the socket until you feel the connector latch into place.

Figure 5 Inserting an SFP Transceiver Module into a Module Socket

Step 7 Press the SFP into the slot firmly with your thumb as shown in Figure 6

Note For SFP transceiver modules equipped with an actuator latch, you must press firmly on both the transceiver faceplate and the actuator button to ensure that the transceiver is properly latched in the socket.

Figure 6 Latching the SFP

Step 8 To verify that the SFP is seated and latched properly:

a. Grasp the SFP as shown in Figure 10 and try to remove it without releasing the latch.

b. If the SFP can not be removed, it is installed and seated properly. If the SFP can be removed, reinsert it and press harder with your thumb, repeating if necessary until it is latched securely into the socket.

Figure 7 Verifying SFP Installation

Note For optical SFP transceiver modules, before removing the dust plugs and making any optical connections, observe the following guidelines:

•Always keep the protective dust plugs on the unplugged fiber-optic cable connectors and the transceiver optical bores until you are ready to make a connection.

•Always inspect and clean the LC connector end-faces just before making any connections. See the Tip on this page for a pointer to a fiber-optic inspection and cleaning white paper.

•Always grasp the LC connector housing to plug or unplug a fiber-optic cable.

Step 9 Remove the dust plugs from the network interface cable LC connectors. Save the dust plugs for future use.

Step 10 Inspect and clean the LC connector's fiber-optic end-faces. See the following Tip for a pointer to a fiber-optic inspection and cleaning white paper.

Tip For complete information on inspecting and cleaning fiber-optic connections, see the white-paper document at this URL:

http://www.cisco.com/en/US/tech/tk482/tk876/technologies_white_paper09186a0080254eba.shtml

Step 11 Remove the dust plugs from the SFP transceiver module optical bores.

Step 12 Immediately attach the network interface cable LC connector to the SFP transceiver module.

Step 13 To connect 1000BASE-T SFP transceiver modules to a copper network, follow these substeps:

Caution To comply with GR-1089 intrabuilding lightning immunity requirements, you must use grounded, shielded, twisted-pair Category 5 cabling.

a. Insert the Category 5 network cable RJ-45 connector into the SFP transceiver module RJ-45 connector.

Note When connecting to a 1000BASE-T-compatible server, workstation, or router, use four twisted-pair, straight-through Category 5 cabling for the SFP transceiver module port. When connecting to a 1000BASE-T-compatible switch or repeater, use four twisted-pair, crossover Category 5 cabling.

b. Insert the other end of the network cable into an RJ-45 connector on a 1000BASE-T-compatible target device.

Step 14 Observe the port status LED:

•The LED turns green when the SFP transceiver module and the target device have an established link.

•The LED turns amber while the STP feature discovers the network topology and searches for loops. This process takes about 30 seconds, and then the LED turns green.

•If the LED is off, the target device might not be turned on, there might be a cable problem, or there might be a problem with the adapter installed in the target device. See the Troubleshooting section of your switch hardware guide for solutions to cabling problems.

Step 15 Reconfigure and reboot the target device if necessary.

Customers interested in purchasing Cisco SFP or the price, please refer to below links:

SFP-10G-LR

GLC-SX-MMD

GLC-LH-SM

WS-X4712-SFP+E module can't put into an R-E chassis ?

Does anyone know why is not possible to put a WS-X4712-SFP+E - module into an R-E chassis?

The module has the same connection to backplane as the WS-X4748-UPOE+E

and this one works in a R-E chassis.

I know the restriction of Cisco that the 4712 is only supported in 4503-E, 4506-E,

4507+E and 4510+E, WS-X4448-GB-SFP, but why?

Are there hardware-restrictions, is the backplane different?

The solution:

The reason is the chassis itself.

The 4712 has a 48 gigabits per-slot capacity. You need the Sup 7E on the R+E chassis to achieve the 48Gbps per slot in order to get a 2.5:1 over-suscription rate.

On the R-E chassis, the 7E defaults to 24Gbps per slot, and the over-subscription ratio increases to 5:1 which was considered unacceptable. Hence we have disabled the working of the 4712 on R-E chassis. It is a chassis limitation.

Compatibility of GLC-SX-MM and GLC-SX-MMD

If I connect a GLC-SX-MM at one end and GLC-SX-MMD at the other end, will the link come up.The difference between the modules is that one supports Digital Optical Monitoring and other does not.

The solution:

As long as you are using the correct patch cable (MM) and your backbone is also MM, then yes.  The GLC-SX-MMD and GLC-SX-MM are compatible.

Cisco GLC-SX-MM is compatible with the IEEE 802.3z 1000BASE-SX standard, operates on legacy 50 μm multimode fiber links up to 550 m and on 62.5 μm Fiber Distributed Data Interface (FDDI)-grade multimode fibers up to 220 m. It can support up to 1km over laser-optimized 50 μm multimode fiber cable.

Cisco GLC-SX-MMD is compatible with the IEEE 802.3z 1000BASE-SX standard, operates on legacy 50 μm multimode fiber links up to 550 m and on 62.5 μm Fiber Distributed Data Interface (FDDI)-grade multimode fibers up to 220 m. It can support up to 1km over laser-optimized 50 μm multimode fiber cable.

WS-X4648-RJ45-E Installation -- Support and Restrictions

WS-X4648-RJ45-E: 48-port, 10/100/1000 Ethernet module

WS-X4648-RJ45-EInstallation –Support and Restrictions

• Supported on by the Supervisor Engine 6-E,

Supervisor Engine 6L-E, and the Supervisor Engine 7-E

• Supported only in the Catalyst 4503-E,  Catalyst 4506-E, Catalyst 4507R+E, and Catalyst 4510R+E switch chassis.

• Can be installed in any non-supervisor engine slot.

WS-X4648-RJ45-E Minimum and Maximum Port Density:

• Catalyst 4503—48/96

• Catalyst 4506-E, Catalyst 4507R+E—48/240

• Catalyst 4510R+E—48/384

• You need a Supervisor Engine 7-E to support more than 240 ports on the Catalyst 4510R-E and Catalyst 4510R+E switch chassis

The similar cisco module WS-X6748-SFP you maybe interested, please CLICK HERE.

Where to buy Cisco GLC-SX-MMD

GLC-SX-MMD, the replacement of GLC-SX-MM, 1000BASE-SX SFP transceiver module, MMF, 850nm, DOM.

The Cisco list price for GLC-SX-MMD is 500 USD, there are many suppliers for this, according to our research on GLC-SX-MMD Price, best price is from, http://www.3anetwork.com/cisco-glc-sx-mmd-price_p1022.html, 145 USD, you save: US$355.00 (71% off), but they are based in Hong Kong, so may take 3 days to reach your country, some other sources for your reference:

1, distributors, like Ingram Micro, Comstor, Tech Data, Redington etc, different countries different distributors, also different price related to your region, partner level and project level, normally around 30%~60% off GPL;

2, http://www.cdw.com/shop/products/Cisco-SFP-mini-GBIC-transceiver-module/2542675.aspx , 368.99 USD, professional and authorized Cisco online supplier, but the price is high, also are not so flexible in cross country sellings.

3, www.router-switch.com/glc-sx-mmd-p-4958.html+&cd=14&hl=en&ct=clnk&gl=us,  160 USD, price a bit high, Hong Kong based, however, their website can not be opened in China, these guys are ranking quite good on google.com, but why their website is not available to their own country customers, interesting.

4, http://www.amazon.com/Cisco-1000BASE-SX-Interface-Converter-GLC-SX-MMD/dp/B008J55IEG, 36.99 USD, good price but frankly speaking Amazon is not professional in Cisco products at all, as can see from their description, also the list price 2995 USD is not correct, if you are located in US, maybe you can try, otherwise better find a professional networking supplier.

5 http://www.networkhardware.com/Cisco/OpticalTransceivers/SFP/GLC-SX-MMD no price on their web, you may send Email to check with them, I think their advantage is they have a big stock for used products.

Cisco 4507 power inline : IEEE PD issues

Found this problem more than 3 times. when we disconnect the cisco ip phone from 4507 switch, and then connect again, it cannot power on any more, when I connect to 4507 switch, "show power inline" command displayed the port is " Ieee PD" cannot displayed the IP Phone 7945... but when I move the cable to Cisco Catalyst 3750, show power inline command, it dispalyed as IP Phone 7945.

We have the same issue in three 4507 switch, no matter what I change the new cable or new IP phone. doesn't work... I don't if the switch 4507 port have some problem or how to reset the power inline to default. or you may have the same problem before when you deployed the cisco IP phone to your network replace PBX phones.

The answer:

Here are some 4507 info:

System image file is "bootflash:cat4500-ipbasek9-mz.122-53.SG1.bin"

cisco WS-C4507R-E (MPC8540) processor (revision 13) with 524288K bytes of memory.

Processor board ID

MPC8540 CPU at 800Mhz, Supervisor V-10GE

Last reset from PowerUp

5 Virtual Ethernet interfaces

248 Gigabit Ethernet interfaces

4 Ten Gigabit Ethernet interfaces

511K bytes of non-volatile configuration memory.

1    48  10/100/1000BaseT (RJ45)V, Cisco/IEEE   WS-X4548-RJ45V+   

2    48  10/100/1000BaseT (RJ45)V, Cisco/IEEE   WS-X4548-RJ45V+  

  3     6  Sup V-10GE 10GE (X2), 1000BaseX (SFP)  WS-X4516-10GE     

4     6  Sup V-10GE 10GE (X2), 1000BaseX (SFP)  WS-X4516-10GE     

5    48  10/100/1000BaseT (RJ45)V, Cisco/IEEE   WS-X4548-RJ45V+   

  6    48  10/100/1000BaseT (RJ45)V, Cisco/IEEE   WS-X4548-RJ45V+   

7    48  10/100/1000BaseT (RJ45)V, Cisco/IEEE   WS-X4548-RJ45V+  

                        Watts used of Chassis Inline Power (-50V)

                        Inline Power Admin  Inline Power Oper

Mod   Model                PS     Device       PS     Device     Efficiency

----  -------------------  ----------------    ----------------    ----------

1    WS-X4548-RJ45V+        222      208         74       69          94

2    WS-X4548-RJ45V+        166      156         63       59          94

3    WS-X4516-10GE            -        -          -        -           -

4    WS-X4516-10GE            -        -          -        -           -

5    WS-X4548-RJ45V+        447      420        148      139          94

6    WS-X4548-RJ45V+        396      372        130      122          94

7    WS-X4548-RJ45V+        396      372        131      124          94

-------------------------  ----------------    ----------------    ----------

       Total                1627     1528        546      513

The issue at Module 5, all this Module 5 cannot provide the PoE now...  G5/* cannot provide the POE.

What's the difference between WS-X4548-RJ45V+ and WS-X4548-GB-RJ45V

WS-X4548-RJ45V+VS WS-X4548-GB-RJ45V:

WS-X4548-RJ45V+ overview:

. 48 ports

. 10/100/1000 (RJ-45)

. Cisco IOS Software Release 12.2(50)SG or later

. IEEE 802.3af/at and Cisco prestandard PoE, IEEE 802.3x flow control

. Bandwidth is allocated across six 8-port groups, providing 1 Gbps per port

group

. Capable of up to 30W of inline power per port

. Enterprise and commercial: designed to power next-generation IP phones,

wireless base stations, video cameras, and other PoE devices that require

power up to 30 watts

WS-X4548-GB-RJ45V Cisco Catalyst 4500 PoE IEEE 802.3af 10/100/1000, 48 Ports (RJ-45), the similar product is WS-X4648-RJ45V+E.

WS-X4548-GB-RJ45V:

. 48 ports

. 10/100/1000 (RJ-45)

. Cisco IOS Software Release 12.2(18)EW or later

. IEEE 802.3af and Cisco prestandard PoE, IEEE 802.3x flow control

. Bandwidth is allocated across six 8-port groups, providing 1 Gbps per port

group

. Enterprise and commercial: designed to power IP phones, wireless base

stations, video cameras, and other IEEE-compliant powered devices.

Difference between the WS-X6748-GE-TX and WS-X6748-SFP

Question: What are the architectural differences between the WS-X6748-GE-TX, WS-X6748-SPF and the WS-X6724-SPF (ports per ASICs, buffers Tx-Rx, fabric connections, etc.)? Also, if someone has information about the oversubscription rate of the cards it would be great.

Answer:  All modules need the Supervisor 720 although i guess you know that !.

The 6748 modules have dual 20Gbps connections to the switch fabric.

The 6724 has one 20Gbps connection to switch fabric.

So for the 48 ports blades they can run 48 x 1Gbps ports with a 40Gbps connection to the switch fabric.

The 24 port blade you can run 24 x 1Gb with a 20Gbps connection to the switch fabric.

So you do get oversubscription but nowhere near as bad as some of the other modules.

As for the buffers etc. rather than just cut and paste from the docs attached is a link for all the modules for the 6500. If you click on the relevant links you can get the stats from there.

http://www.cisco.com/en/US/products/hw/switches/ps708/products_relevant_interfaces_and_modules.html

The similar cisco module you maybe interested, please click the below links:

WS-X4712-SFP+E

WS-X4548-RJ45V+

Guidelines for How to Buy Cisco switch

1 The core of local area network

For the network core, recommend the use of Catalyst 6500 (family 6500 catalyst Home Edition) to manage the LAN switch module. The tool provides the performance and the application aspect enough flexibility to cope with the core, and the layout of local area network, the main market, it also supports the integration of network services and the elastic properties of this kind of switch is the demand for large enterprises, especially in the users of the financial, education and medical care field.

"6500 Catalyst provides technical services to the best products, including sub-200-millisecond based (latency less than two hundred MS) controller VSS (virtual storage system, a video storage system) and quick failover enhanced version of the upgrade (EFSU)function, and Cisco IOSNetFLow have the same visibility rich," Conover said. "Catalyst 6500can also provide support for upward and downward compatibility, to protect the user'spurchase benefit."

2 Local area network access switch

Catalyst home 2K, 3K and 4K

For access to the LAN, recommended Cisco 3750. This product is popular because of its media applications function is very rich, such as video, it uses comprehensive simulation flow and Qos (quality of service, a solution to the problem of network delay andblocking technology) energy efficiency assessment, to ensure a good network quality. It can also be intelligent identification and video priority access to bandwidth guaranteed the userport. In addition, the network administrator can also monitor and through to the trackingnetwork video flow to identify any that may lead to the node flash or delay. Users can also infacing the future bandwidth demands greater, the Gigabit Ethernet upgrading the original to Gigabit ethernet.

3 Small switches

In a small switch products, recommended by Catalyst Switch 2960-C and 3560-C. These small switches provide extended services, can help users to simplify problems whenever and wherever possible to construct local area network has to face, and allow users to stay away from trouble wiring clutter.

About the switch selection and deployment tips

If you're more like fixed switch, then Catalyst 3750-X more appropriate; while Catalyst 4500Eis those who tend to modular product users preferred.

Catalyst 2960-S can be used alone, also can be used as part of combination of settings toconfigure (the optional combination module supports up to four switches to paralleloperation). But please note, the most suitable product or provide the highest one hundred and ninety-two access port for wiring cabinet branch network or space constraints. Similarly,Catalyst 3750-X switches can also be combined (maximum support nine switches to paralleloperation), and the most ideal working state is to support branch network or enterprise levelwiring requirements. In addition, Catalyst 3560-X actually is 3750-X twenty-four or forty-eight port independent version, used for small branch network of job requirements.

In the deployment of Catalyst 2960-S, 3560-X or 3750-X switch, intelligent Conover users are advised to use Cisco installation function. This technology can automatically configure theswitch through IOS software mirroring the Cisco, without user intervention. It adopts the dynamic IP address assignment and pre configured switch navigation to simplify the installation process. The switches are using automatic intelligent node of this feature toautomatically configure each device connected to the node, but also other equipment automatic detection of access network.

3Anetwork.com is a world leading Cisco networking products wholesaler, we wholesale original new Cisco networking equipments, including Cisco Catalyst switches, Cisco routers, Cisco firewalls, Cisco wireless products, Cisco modules and interface cards products, 3Anetwork.com are most competitive on Cisco switches, like Cisco 2960 switches, Cisco 3560V2 3560X switches, Cisco 3750V2 3750X switches. Our customers include Cisco resellers, system integrators, ICT companies, online retailers etc. Right now most of our sales are contributed by regular customers. Our CCIE headed technical team can provide network design, products installation and configuration, trouble shooting etc.More information, please view: http://www.3anetwork.com

Difference between network-clock-select and network-clock-participate

What is the difference between network-clock-select & network-clock-participate?

What’s the network-clock-participate

To allow the ports on a specified network module or voice/WAN interface card (VWIC) to use the network clock for timing, use the network-clock-participate command in global configuration mode. To restrict the device to use only its own clock signals, use the no form of this command.

network-clock-participate [slot slot-number | wic wic-slot | aim aim-slot-number]

no network-clock-participate [nm slot | wic wic-slot]

Usage Guidelines

This command is used for ATM segmentation and reassembly or digital signal processing and Cisco 3660, Cisco 3725, and Cisco 3745 routers.

This command applies to any network module with T1/E1 controllers to provide clocks from a central source (MIX module for the Cisco 3660) to the network module and to the port on the network module. Then that port can be selected as the clock source with the network-clock-select command to supply clock to other ports or network modules that choose to participate in network clocking with the network-clock-participate command. This command synchronizes the clocks for two ports.

On the Cisco 3700 series, you must use the network-clock-participate command and either the wic wic-slot keyword and argument or the slot slot-number keyword and argument.

What’s the network-clock-select

To name a source to provide timing for the network clock and to specify the selection priority for this clock source, use the network-clock-select command in global configuration mode. To cancel the network clock selection, use the no form of this command.

Cisco 2600 Series and Cisco 3660 with MIX Module

network-clock-select priority {t1 | e1} slot/port

no network-clock-select priority {t1 | e1} slot/port

Cisco MC3810

network-clock-select priority {serial 0 | system | bvm | controller}

no network-clock-select priority {serial 0 | system | bvm | controller}

Usage Guidelines

When an active clock source fails, the system chooses the next lower priority clock source specified by this command. When a higher-priority clock becomes available, the system automatically reselects the higher-priority clock source.

Cisco 2600 series, Cisco 3660, and Cisco 3700 series

This command is used on Cisco 2600 series and Cisco 2600XM with AIMs installed or on the Cisco 3660, Cisco 3725, or Cisco 3745 with Multiservice Interchange (MIX) modules installed. This command names a controller to provide clocking signals to the backplane, which then provides the names to all the network modules that are participating in network clocking.

Cisco MC3810

This command applies to Voice over Frame Relay, Voice over ATM, and Voice over HDLC on the Cisco MC3810. Use the network-clock-select command to establish the clock-selection priority when there are multiple sources of line (network) clocking in a Cisco MC3810. Possible sources of line clocking for the Cisco MC3810 are the BRI voice module (BVM), the multiflex trunk module (MFT), and a serial port configured for clock rate line.

Hope can you help to learn more about the Cisco networking products.

The most popular Cisco 2960 switch: WS-C2960S-48TS-L, WS-C2960-24TT-L, competitive price on 3anetwork.com.

Source: http://www.cisco.com/en/US/docs/ios/12_3/vvf_r/vrg_n1_ps1839_TSD_Products_Command_Reference_Chapter.html#wp1001437

WS-X6548-GE-TX VS WS-X6748-GE-TX

The difference between WS-X6548-GE-TX & WS-X6748-GE-TX

WS-X6548-GE-TX uses Centralized Bus Forwarding as opposed to CEF720 Bus Forwarding used on WS-X6748-GE-TX.

The CEF720 uses 2x20Gbps connection to the switch fabric, which on this case is the Sup Module (no need for a switch fabric module).

WS-X6548-GE-TX is only 1MB buffer per port while WS-X6748-GE-TX is 1.3MB buffer per port.

WS-X6548-GE-TX is a hybrid, it supports backplane connection in switch fabric or bus mode while WS-X6748-GE-TX can only support switch fabric.

Personally, I see WS-X6748-GE-TX, the module of choice if you have a Sup720 since it uses the ideal Bus Forwarding for this hardware.

WS-X6748-GE-TX: Supervisor Engine 720, 720-10GE and 2T-10GE.

The WS-X6748-GE-TX is not supported in the Catalyst 6503 switch chassis. The WS-X6748-GE-TX module can occupy any slot in any other Catalyst 6500 or Catalyst 6500-E chassis except the Catalyst 6513 chassis where the module must be installed in slots 9-13. The module does not power up when it is installed in slots 1-8.

WS-X6748-GE-TX ships with the WS-F6700-CFC daughter card factory-installed. The module can be upgraded in the field to support the WS-F6700-DFC3A, WS-F6700-DFC3B, WS-F6700-DFC3BXL, WS-F6700-DFC3C, WS-F6700-DFC3CXL, WS-F6K-DFC4-A, or the WS-F6K-DFC4-AXL daughter cards.

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Cisco Switch IOS versions 2960S

Can I Add Cisco 2901 as MGCP Gateway to CUCM 7.2.1 Business Edition

I am in the process to buy a new Cisco 2901 ISR2 with a new generation T1/E1 card (VWIC3-1MFT-T1/E1) to replace our old Cisco 2811. The router has attached a PRI line for VoIP. The old 2811 is registered as a MGCP gateway to our CUCM. We have a CUCM 7.2.1 Business edition which is holding the entire company VoIP system.

My question is: can I register in CUCM the new 2901 as a MGCP gateway? In the drop-down list  (when I am trying to add the gateway) I cannot find the 2901 version of Cisco. Only 28xx. Does anyone have encounter this problem?

The answer:

Yes you can. You just need to upgrade that 7.1.2 to latest 7.1.5, otherwise the device model (which is newer than version 7.1.2) will not appear as an option, it is just not there in the database:

Table 4. Cisco products Unified Communications Routers with Cisco Unified Communications Manager Minimum System Requirements Using MGCP

http://www.cisco.com/en/US/prod/collateral/routers/ps10536/data-sheet-c78-729824_ps13303_Products_Data_Sheet.html