Connecting two smart serial cables on WICT2 cards between routers

[Clay Plaga]

I have a test Network that I'm using for my certifications. I have an1841 router and a 2811 router. I have the two routers connected with a WAN connection using a smart serial cable. I am using a WIC2T card in both routers. I noticed the connection is very slow. Is there a command I can use to see what the data rate is of this WAN connection?  Also, I noticed there are two serial connectors on the WICT2 cards. Can I connect another smart serial cable to the other connector on the other side between the routers and double the WAN speed? Is that a form of link aggregation?

Thank you

[Richard Burts · Accepted solution]

That card does support 2 connections. So I do not see any reason why you could not establish a second serial connection. Whether that would double the WAN speed is a different question. If you configure both connections for PPP encapsulation then you probably could use Multi Link PPP. MLPPP combines the two physical links and treats them as a single logical link and would come fairly close to double the speed. Without MLPPP you would configure each link with its own independent IP subnet. You could use static routing or use dynamic routing protocol to send traffic over each of the links. You would have 2 equal cost paths and would have load sharing over 2 separate links which would increase the effective throughput, but it would be less than double the speed.

HTH

Rick

[Clay Plaga]

Thank you for the information. As I said, I am just beginning my Cisco studies. I configured the WAN connection from a YouTube video. I will learn how to do this MLPPP WAN configuration. I need to purchase a new smart serial cable. I also just noticed that the smart serial cable has DCE on one end, and DTE on the other end. Am I correct that the DCE(clocking) side has to be connected to the router that is configured as the DCE clocking side? It's working, so it must be configured correctly. Is there a way to find out what the data rate of the WAN connection is? I will try your suggestion.

Thanks.

[Richard Burts]

You are welcome. Yes there is a DTE and a DCE end of the cable and yes the DCE end needs to be connected to the interface configured with clocking. Here is a link that you may find helpful about MLPPP

https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/wan_mlp/configuration/xe-3s/wan-mlp-xe-3s-book/dia-media-ind-multi-ppp-xe.html#GUID-B58EF654-F2B2-4CB7-9D8C-1F71F63B04AB

There are a couple of ways to find the data rate of the link. There are some show commands that you could use. Be aware that the output of show interface will show a bandwidth but it is showing a default value based on the type of interface and probably is not the actual data rate of your interface. There are some show commands that show the serial controller and if you look at those on the DCE side you should find the correct data rate. And the easy way to find the data rate is to look at what is configured for clocking on the DCE router.

Thank you for marking this question as solved. This will help other participants in the community to identify discussions which have helpful content. This community is an excellent place to ask questions and to learn about networking. I hope to see you continue to be active in the community. Good luck as you continue your Cisco studies.

HTH

Rick

[Clay Plaga]

I will work on this as soon as I get home. I found some MLPPP sample configurations and I will add the second smart serial cable. Thank you for the information, I really appreciate it.