Re: What does "bridge" mean?

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From: Ryan Hanisco (rhanisco_at_flagshipis.com)
Date: 02/03/05 

Date: Thu, 3 Feb 2005 08:23:08 -0600

Larry,

In this case the "bridge" your friend is referring to is not a wireless
bridge at all. It sounds like he has a VPN or Tunnel set up between the
two routers. This allows the two separate networks to act as though they
are really one. Both end points can have the same subnet, as long as the
external interfaces (the tunnel endpoints) are not in that subnet and can
route to one another. I will point out, that in this case, you will usually
keep them in different subnets and turn on routing between them -- though it
is valid to keep them in the same subnet if you want. Putting them in
different subnets make sure that broadcasts and the like do not cross your
WAN link.

Go to the Cisco site and look up:
Router VPN Tunnel
GRE Tunnel
Cisco Easy VPN Client 

-- 
 Ryan Hanisco
MCSE, MCDBA
Flagship Integration Services
"Larry David" <MysteriousAilment@HealthyChoice.org> wrote in message 
news:q6adnVkL-ffxHpzfRVn-rw@giganews.com...
> Hi,
>
>    I currently have two networks in two locations. They are connected by a
> T1 "local loop" with a Cisco router on each end of the loop. The two
> networks have an address scheme of 192.168.0.0/24 and 192.168.1.0/24
> respectively.
>
>    A friend of mine has a similar situation to mine. He has two networks 
> in
> two locations connected by a T1 "local loop" with a Cisco on each end --  
> but
> in HIS case, all computers in both locations are on the same logical
> network: 192.168.112.0/24. I don't understand how this can be, but he said
> that the person who configured his Ciscos set up a "bridge."
>
>    Could someone explain to me what is a bridge is conceptually? This 
> whole
> concept seems weird to me because it seems like he would end up having all
> kinds of broadcast messages (arp, dhcp, netbios, etc.) going across the 
> that
> slow T1 link since all of the machines are on the same logical network.
> Clearly this can't be what my friend's network engineer intended, is it?
>
>    Could someone give me the scenarios where MY configuration is 
> preferable
> and scenarios where HIS bridge configuration is preferable? I'm just 
> asking
> out of idle curiosity. I like to know things work -- even though I'm
> (obviously) not a network professional. I'm funny that way! Any comments
> would be appreciated.
>
> Thanks!
>
>

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