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Switch terms

Hello all.

I am supposed to fill an excel sheet with information on some Cisco switch models, i understand most of the terms but i have some which i do not understand, can someone help me on the meaning and examples ( in reference to the WS-C3750X-48P-L model or any similar model ) of the following:

CVR/X2 MODULE SUPPORT

REQUIRED   IOS FOR IPV6 SUPPORT

MINIMUM   IOS FOR GBIC SUPPORT

WIRE   SPEED

STACKING   CAPACITY

thanks


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Re: Switch terms

CVR is a twingig module converting each 10 Gig X2 interface into two Gig SFP ports.

CVR-X2-SFP

TwinGig Converter Module

http://www.cisco.com/en/US/prod/collateral/switches/ps5718/ps7077/product_data_sheet0900aecd805bbee3.html

IPv6 support for 3750-x is from 12.2(53)SE2 and upwards according to feature navigator.

GBIC is not used for 3750 to the best of my knowledge. It is an legacy interface.

http://www.cisco.com/en/US/tech/tk389/tk214/technologies_tech_note09186a0080094863.shtml#cat3750k

Wire speed means if the interface can transmit/receive at the physical speed. So if interface is Gigabit it should be able to transmit/receive at full speed.

Stacking capacity is how much traffic can be sent via backplane through stacking cable. Catalyst 3750-x has 16 Gbps per stacking cable which is 32 Gbps in each direction for a ring or 64 Gbps if talking about fully utilized on both directions.

http://www.cisco.com/en/US/prod/collateral/switches/ps5718/ps5023/prod_white_paper09186a00801b096a.html

Post edited after input from Joseph.

Daniel Dib
CCIE #37149

Please rate helpful posts.

Daniel Dib CCIE #37149 Please rate helpful posts.
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Silver

Re: Switch terms

CVR is a twingig module converting each 10 Gig X2 interface into two Gig SFP ports.

CVR-X2-SFP

TwinGig Converter Module

http://www.cisco.com/en/US/prod/collateral/switches/ps5718/ps7077/product_data_sheet0900aecd805bbee3.html

IPv6 support for 3750-x is from 12.2(53)SE2 and upwards according to feature navigator.

GBIC is not used for 3750 to the best of my knowledge. It is an legacy interface.

http://www.cisco.com/en/US/tech/tk389/tk214/technologies_tech_note09186a0080094863.shtml#cat3750k

Wire speed means if the interface can transmit/receive at the physical speed. So if interface is Gigabit it should be able to transmit/receive at full speed.

Stacking capacity is how much traffic can be sent via backplane through stacking cable. Catalyst 3750-x has 16 Gbps per stacking cable which is 32 Gbps in each direction for a ring or 64 Gbps if talking about fully utilized on both directions.

http://www.cisco.com/en/US/prod/collateral/switches/ps5718/ps5023/prod_white_paper09186a00801b096a.html

Post edited after input from Joseph.

Daniel Dib
CCIE #37149

Please rate helpful posts.

Daniel Dib CCIE #37149 Please rate helpful posts.
Super Bronze

Re: Switch terms

Disclaimer

The  Author of this posting offers the information contained within this  posting without consideration and with the reader's understanding that  there's no implied or expressed suitability or fitness for any purpose.  Information provided is for informational purposes only and should not  be construed as rendering professional advice of any kind. Usage of this  posting's information is solely at reader's own risk.

Liability Disclaimer

In  no event shall Author be liable for any damages whatsoever (including,  without limitation, damages for loss of use, data or profit) arising out  of the use or inability to use the posting's information even if Author  has been advised of the possibility of such damage.

Posting

Stacking capacity is how much traffic can be sent via backplane through stacking cable. Catalyst 3750-x has 32 Gbps per stacking cable which is 64 Gbps in each direction or 128 Gbps in marketing speak.

http://www.cisco.com/en/US/prod/collateral/switches/ps5718/ps5023/prod_white_paper09186a00801b096a.html

My understanding of the StackWise Plus, it offers just 64 Gbps across both stack ports.  Cisco's "marketing speak" usually describes StackWise as having 32 Gbps and StackWise Plus 64 Gbps.  Also from your reference:

Technology Overview

Cisco  StackWise technology provides an innovative new method for collectively  utilizing the capabilities of a stack of switches. Individual switches  intelligently join to create a single switching unit with a 32-Gbps  switching stack interconnect. Configuration and routing information is  shared by every switch in the stack, creating a single switching unit.  Switches can be added to and deleted from a working stack without  affecting performance.


Bidirectional Flow

To  efficiently load balance the traffic, packets are allocated between two  logical counter-rotating paths. Each counter-rotating path supports 16  Gbps in both directions, yielding a traffic total of 32 Gbps  bidirectionally. The egress queues calculate path usage to help ensure  that the traffic load is equally partitioned.

StackWise Plus

StackWise  Plus is an evolution of StackWise. StackWise Plus is only supported on  the Cisco Catalyst 3750-E and Catalyst 3750-X switch families. The two  main differences between StackWise Plus and StackWise are as follows:

1.  For unicast packets, StackWise Plus supports destination striping,  unlike StackWise support of source stripping. Figure 9 shows a packet is  being sent from Switch 1 to Switch 2. StackWise uses source stripping  and StackWise Plus uses destination stripping. Source stripping means  that when a packet is sent on the ring, it is passed to the destination,  which copies the packet, and then lets it pass all the way around the  ring. Once the packet has traveled all the way around the ring and  returns to the source, it is stripped off of the ring. This means  bandwidth is used up all the way around the ring, even if the packet is  destined for a directly attached neighbor. Destination stripping means  that when the packet reaches its destination, it is removed from the  ring and continues no further. This leaves the rest of the ring  bandwidth free to be used. Thus, the throughput performance of the stack  is multiplied to a minimum value of 64 Gbps bidirectionally. This  ability to free up bandwidth is sometimes referred to as spatial reuse.  Note: even in StackWise Plus broadcast and multicast packets must use  source stripping, because the packet may have multiple targets on the  stack.

This I've taken to mean, the bidirectional bandwidth of the pair of StackWise Pluse stack cables is 32 Gbps, duplex, and that each stack port is 16 Gbps, duplex.

Regarding the "minimum value", this is in reference to StackWise Plus's "spatial reuse", which allows a stack ring, of more than two members, to increase its aggregate bandwidth.  More details of this can be found in (Cisco's) RFC 2892.

Silver

Re: Switch terms

Thanks for clearing that up Joseph, I have edited my post.

Daniel Dib
CCIE #37149

Please rate helpful posts.

Daniel Dib CCIE #37149 Please rate helpful posts.
New Member

Switch terms

Hello Daniel.

The link on the Cisco website to see the switch models that support TwinGig is not available, i wanted to see if the 3750X series switches have support for TwinGig modules. Can you please help?

regards.

Super Bronze

Re: Switch terms

Disclaimer

The   Author of this posting offers the information contained within this   posting without consideration and with the reader's understanding that   there's no implied or expressed suitability or fitness for any purpose.   Information provided is for informational purposes only and should not   be construed as rendering professional advice of any kind. Usage of  this  posting's information is solely at reader's own risk.

Liability Disclaimer

In   no event shall Author be liable for any damages whatsoever (including,   without limitation, damages for loss of use, data or profit) arising  out  of the use or inability to use the posting's information even if  Author  has been advised of the possibility of such damage.

Posting

The link on the Cisco website to see the switch models that support TwinGig is not available, i wanted to see if the 3750X series switches have support for TwinGig modules. Can you please help?

regards.

No it does not. First the 3750X uses SPF or SPF+ (with 10G fiber module), not X2.  Second, since SPF+ will run at gig or 10g, there's really not a need.

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