On Saturday 08 January 2005 10:19 am, Chuck Hast wrote:
> On Sat, 8 Jan 2005 08:55:43 -0500, SOTL <sotl155360@earthlink.net> wrote:
> > On Saturday 08 January 2005 04:01 am, Paul M Foster wrote:
> > > On Fri, Jan 07, 2005 at 09:28:14PM -0500, SOTL wrote:
> > > > Hi All
> > > >
> > > > What is the difference between a wireless router and a wireless
> > > > bridge? Just so I do not confuse people I know a router goes on the
> > > > line side and the bridge goes on the computer side but really is the
> > > > difference?
> > >
> > > Note: I'm a neophyte to this area. I've set up several simple networks
> > > and know something about the theory of this area. I've never seen or
> > > used a bridge but I know the definition of one. So feel free to correct
> > > me. I'll also use this opportunity to ask questions of the more
> > > knowledgeable in the group. Here's my understanding:
> > >
> > > Bridges are specialized routers, designed to connect two or more
> > > networks or LANs. They use info from the MAC layer (MAC addresses?) to
> > > route packets.
> > >
> > > Routers are more general purpose. They make decisions or where to route
> > > packets based partially on info from higher up in the protocol stack
> > > (IP addresses?). They can be made to function as bridges, though
> > > perhaps less efficiently.
> > >
> > > There are two factors at work. The first is the connection between IP
> > > address and machine names, and the ability to resolve machine names
> > > into addresses. This is handled either by a populated /etc/hosts file
> > > (which contains the names and addresses of local machines), or access
> > > to an active local DNS server. In the latter case, the DNS server
> > > serves to translate machine names into IP addresses to the best of its
> > > ability.
> > >
> > > The second factor is the routing of packets once the IP addresses are
> > > known. The "route -n" command will show you what routing decisions will
> > > be made on the machine it's run on. Your local machine will likely know
> > > how to route all traffic on your LAN directly to the machines involved.
> > > That is, the "route -n" command shows that for local addresses, there
> > > is no gateway; packets to those addresses are routed directly. Any
> > > other addresses will go to a "gateway" router somewhere on your
> > > network, which shows on a separate line of the "route -n" command.
> > >
> > > If your network is like mine, you've got a router for the LAN. It
> > > accepts packets for addresses my local machine doesn't know how to deal
> > > with. It knows how to address local traffic. But for any other traffic,
> > > it has its own "gateway" route, which is to the DSL modem. The DSL
> > > modem does whatever handwaving it needs to to get internet packets
> > > where they're going.
> > >
> > > Since part of specifying a route with the route command also entails
> > > specifying what type of addresses will go on that route, you could
> > > specify a secondary gateway for any traffic going to a different LAN or
> > > network segment. That gateway would then hand off traffic to the proper
> > > hosts on its network segment.
> > >
> > > So the point here is that, while a bridge would directly route traffic
> > > to specific machines on different network segments, a router whose
> > > routing tables are properly set up (with a separate gateway on the
> > > other network segment(s)) could perform the same function. It mainly
> > > depends on how your routes are set up.
> > >
> > > Right?
> > >
> > > Paul
> >
> > Thanks Paul
> >
> > If I get the issue correct it is a matter of package routing and what is
> > allowed to pass, basically a firewall and routing issue.
> >
> > If that is correct then if all firewall features were nulled out then
> > could one could a router be used for a bridge on a simple network
> > consisting of one bridge/router connected to one computer and one router
> > connected to the eathernet line side.
>
> One other thing to take into account is the layout of the RF part of the
> system. Normally wireless routers are designed to connnect to user gear (RF
> Nic's) or real bridges, if you are modifying a router to work as a bridge
> you need to make sure that the RF piece can be changed so as to act like a
> subservient device to the router rather than a router controller device.
>
> Wireless lan on the RF side operates in two modes
> 1. Multi-point to multi-point or Peer to peer, this is where you do
> not have a router or
> access point through which all devices operate through
> 2. Point to multi-point which is the way most of us operate these
> things, one device
> is a access point/router and the other devices communicate through it.
>
> If you use a router as a bridge it must be able to change from a access
> point to a user type device which is how the router views it as a radio.
> The router is looking
> for user devices and will not see a router device unless that device
> can be made to
> appear as another user device on the RF LAN.
Now I am more confused than I was. The issue to me is not clear. So let me
explain what we have and what I need and then maybe someone can advise me.
There are 3 existing computers in our second office. Two can communicate with
each other and with the outside world by wireless. One, mine, can not
communicate with the other two computers as that is not desirable from an
employment perspective. I can communicate with the outside world. If I added
a fourth computer with a fourth wireless router/bridge it would need to be
set so that it could not communicate with any other computer by wireless only
communicating with the outside world. A firewall is not desirable in this
router/bridge as the system to be connected would be a SuSE 9.2 which as you
are aware of has internal firewall capabilities nor would normal routing
action be required only straight in straight out.
Under these circumstances can a wireless router [normally used to connect to
the line side] be used as a wireless bridge [normally connected to the
computer side]?
Thanks
Frank
-----------------------------------------------------------------------
This list is provided as an unmoderated internet service by Networked
Knowledge Systems (NKS). Views and opinions expressed in messages
posted are those of the author and do not necessarily reflect the
official policy or position of NKS or any of its employees.
This archive was generated by hypermail 2.1.3 : Fri Aug 01 2014 - 20:07:05 EDT