PPP+RADIUS - routing subnets to end users - Framed-Route vs. Framed-IP-Netmask

2010-03-08 Thread Erik L
Scenario: with the help of RADIUS, routing subnets to end users connecting via 
PPP.

Discussion: pros/cons of using Framed-IP-Address+Framed-Route versus 
Framed-IP-Address+Framed-IP-Netmask.

We're talking here in generic terms, so as far as the behaviour of the LNS or 
access concentrator or whatever else is receiving the Access-Accept and 
terminating the ppp session, we're assuming more or less sane behaviour, 
roughly as follows. In the first alternative, the IP address on the ppp link is 
outside the subnet indicated by Framed-Route and one or more subnets are routed 
via the link; one such subnet per Framed-Route attrib. In the second 
alternative, the one subnet routed is that which contains the Framed-IP-Address 
and is as large as the Framed-IP-Netmask indicates. 

I'm arguing to a colleague that the first alternative is better, non-/32 
netmasks on a ppp link make no sense (since netmasks on point-to-point links 
don't matter anyway), that the second alternative doesn't allow users to make 
use of their allocated space as easily and effectively as the first 
alternative, and that the second alternative is limited to routing one subnet 
(though you might be able to mix Framed-IP-Netmask and Framed-Route together?). 

Comments? How are others doing it and why?

Erik



Re: PPP+RADIUS - routing subnets to end users - Framed-Route vs. Framed-IP-Netmask

2010-03-08 Thread George Carey
We've always considered the WAN and LAN to be different objects so our history 
is to prefer the method you think is 'better.' Seems this model has been around 
since the dialin days.

We also have customers with multiple routes so it seems a logical separation. 
Failover might be a bit more flexible too since you can control some parameters 
of the Framed Route.

I know some people use RFC1918 addresses for WAN which might be a factor (we do 
not).

Perhaps in some network strategies the lines between WAN and LAN may be a bit 
more blurred than ours.

George


On Mar 8, 2010, at 6:10 PM, Erik L wrote:

 Scenario: with the help of RADIUS, routing subnets to end users connecting 
 via PPP.
 
 Discussion: pros/cons of using Framed-IP-Address+Framed-Route versus 
 Framed-IP-Address+Framed-IP-Netmask.
 
 We're talking here in generic terms, so as far as the behaviour of the LNS or 
 access concentrator or whatever else is receiving the Access-Accept and 
 terminating the ppp session, we're assuming more or less sane behaviour, 
 roughly as follows. In the first alternative, the IP address on the ppp link 
 is outside the subnet indicated by Framed-Route and one or more subnets are 
 routed via the link; one such subnet per Framed-Route attrib. In the second 
 alternative, the one subnet routed is that which contains the 
 Framed-IP-Address and is as large as the Framed-IP-Netmask indicates. 
 
 I'm arguing to a colleague that the first alternative is better, non-/32 
 netmasks on a ppp link make no sense (since netmasks on point-to-point links 
 don't matter anyway), that the second alternative doesn't allow users to make 
 use of their allocated space as easily and effectively as the first 
 alternative, and that the second alternative is limited to routing one subnet 
 (though you might be able to mix Framed-IP-Netmask and Framed-Route 
 together?). 
 
 Comments? How are others doing it and why?
 
 Erik
 



smime.p7s
Description: S/MIME cryptographic signature