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Ethernet Wan - remote office

I need to help trying understand something and I wish someone can help me. We have a remote office and we are thinking about using an ethernet wan service for connecting the 2 remote office together.. The ethernet service is another solution like a T1 or frame except the bandwith for greater.. My question is this..

When the ethernet service company installes the wan they give you a RJ45 connector where you can connect this right into your switch. So Site A plugs the RJ45 into the switch and Site B plugs the RJ45 into there switch.. Now the 2 are connected via etherent. Here is my problem.. Site A has a subnet of 192.168.169.0/255.255.255.0 . Site B has a subnet of 192.168.0.0/255.255.255.0.. how can they talk to each other if they are connected right into the switch.. Is it a VLAN thing on the switch.. Can this even work?

If the above does not work then do I need to plug the RJ45 into a router or firewall to direct he traffic?.. If I need to buy a router can I just place it inside the networks ?What do I need to do to make this work..

tk

Reply to
toms1616
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The witches could work provided the are layer 3. What model switches?

Sounds like you are using LRE. What has yoru service provider siad about routing and connecting teh 2 sites?

Reply to
larkspur

you need to route between the 2 subnets. Easiest way is probably to put a layer 3 switch at 1 or both ends of the WAN link, and route on the ports used for the WAN service.

layer 3 switches are much cheaper than routers per Mbps of thruput if everything is Ethernet.

Also, in your case the switch can also do any internal routing, or provide extra ports - unless the router is there anyway for other things, and has the spare port / capacity.

A lot of modern stackable switches are layer 3 - in cisco speak you need a minimum of a Catalyst 3560, other suppliers such as Foundry, Nortel, HP have equivalent boxes.

Reply to
stephen

Tk

On Site A (192.168.169.0 subnet) is have Nortel BayStack 5520 switch.. On Site B they on an old 3com switch ( most likely not layer 3).. Do I need to upgrade the switch on Site to a layer 3?

If I plug in the etherent service on the notel switch how can I route though the port that the ethernet service is plugged into?

what is LRE? thanks for your help..

Reply to
toms1616

LRE - Is Long Reach Etherent. This type of technology is common in major meto areas.

Reply to
larkspur

no - you only need L3 at 1 end of the link, although if you have a WAN fault having no L3 at the remote site makes debugging more difficult - "their" subnet goes all the way to the central site L3 switch.

Also all broadcasts from the remote site will cross the WAN - shouldnt be a major issue or significant bandwidth hog under normal conditions.

Reply to
stephen

If you want to keep your current subnet structure, you will definately need to do some L3 routing. Minimally you will need only one router. (as others have mentioned here) To eliminate unwanted broadcasts on the WAN, you'll want to have two.

Depending on what the level of traffic (and the amount of $$) you expect to have between the two sites, you might try routing them with a small router like the Cisco 1605-R. They can be obtained on eBay now from between $50 and $100.

If there isn't too many machines on one subnet or the other, you

would, however, be transferring all the broadcasts from each site to the other site. Again, not a problem if there's only a few machines.

J.Cottingim

Reply to
jcottingim

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