Can some1 explain to me about Modules/Ports?

[rachelhor]

Hi,

I went to cisco web-site to search for routers, and I see routers with switching ports and functions.

Then I went to search for switches, and I see switches with routing functions.

Now, I'm very confused. It seems like there is no longer a distinct difference between routers and switches. Are they now the same? What is the difference?

Also, when I search for router modules, (eg. 2800 or 3800 series) I see descriptions like

- Etherswitch ports (FE switch ports)

- Ether WAN ports (FE WAN ports)

Can some1 explain to me what are the differences between Etherswitch ports, EtherWAN (FE WAN) ports and FE LAN ports?

In the past, when I was using 2600 series routers, they come with on-board FE ports.

So, are these on-board FE ports on 2600 routers equivalent to Today's Etherswitch ports?

Also, can routing protocols be sent over Etherswitch ports and EtherWAN ports?

So, if I am to connect 2 routers (2800/3800 series)for 2 different networks but are geographically close by. Do I use Etherswitch ports or EtherWAN ports?

Finally, when I was using 2600 routers, I only need to find an 100FX module. What is the equivalent module should I use for 2800/3800 series routers if I want a fiber port?

Hope some1 can help me.

Thank you.

[amit-singh]

Hi,

yes, there are Layer 3 switches which does almost the same functionlity even at greater backplane speed and more CPU processing power except that you cannot terminaye you WAN connectiions like Serial, ISDN, ASYNC, ISDN PRI, T1/E1 lines. There are few of the switches even with the T1 and E1 modules and you can terminate your lines directly.

The diffrence between the ports are, etherswitch is a layer 2 module that you can put into the chassis which does the normal layer 2 functionality and you can even define the VLAN and VTP functionality in the router. The ether WAN port and the FE port are the Layer-3 ports which does only the L-3.

On board, FE ports on the chassis are different then the etherswitch ports. I have not tried whether we can define the ports in the etherswitch as the l3 ports or not, may be someone else can define that.

You can use any of the ports for your N/W connectvity depending on ther design and requiremnt.

NM-1FE-FX-V2, is the module that you can use in the 3800 chassis. No fiber module for 3800 Yet.

Please check the link :

http://www.cisco.com/univercd/cc/td/doc/product/access/acs_mod/index.htm

HTH,

-amit singh

[rachelhor]

Hi,

So ..... am I right to understand that:-

q1) routing protocols (RIP/OSPF/EGP etc) CANNOT be sent over the Etherswitch ports?

q2) routing protocols can only be sent over layer 3 ports?

q3) so Cisco has re-named all their layer 3 FE ports as "Ethernet Switch HWIC"?

q4) Under what circumstances do I use Etherswitch ports?

q5) Finally, after checking out the link you mentioned for Cisco 2800 series routers, can you kindly explain what is the difference between

a)"Ethernet Switching Network Module" (example NM-16ESW) and

b)"Ethernet Switch High Speed WAN Interface card" (example HWIC-4ESW)

q6) Which of the above (a) or (b) is the layer 3 and layer 2 ports?

I'm confused because both (a) and (b) have the word "Ethernet Switch" in the description.

Thank you very much.

Hope to get some replies asap, because I need to buy some routers and switches urgently.

[amit-singh]

Hi,

Q1, No, routing protocls can be sent over the L2 ports. Think of using a layer3 switch like 3550 and connected via trunk.

Q2. As explained, both L2/L3.

Q3. No

Q4 If you have a small office with less no of users, then you can use an etherswitch module to provide the L2 connectvity.

I think both are L2's and the only differnce is the number of ports offered in both of the modules. Also there are specfic slots in which you can use YOUR NM and HWIC modules.

http://www.cisco.com/en/US/products/ps5855/products_data_sheet0900aecd8016bf0b.html

http://www.cisco.com/warp/public/cc/pd/rt/2600/prodlit/2600x_ds.pdf

I am not sure but may be someone else can put some more light on this.

Kevin,Greg,Rick,Shanky any one pls.

regards,

-amit singh