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Cisco 2600XM and external eth DSL modem

Hello I would like to ask you how to configure a Cisco 2600XM (with 2 FE ports) with an ADSL Line (RFC1483) and an external eth modem.

I have a 2651XM, on FE0/0 I have an external ETH modem, on FE0/1 I have the LAN side 192.168.0.254/24

With an ADSL Wic I configured the cisco as the following:

interface FastEthernet0/0 description Interfaccia verso la backbone interna ip address 172.16.0.241 255.255.254.0 no ip redirects no ip proxy-arp ip nat inside ip virtual-reassembly standby delay minimum 20 reload 20 standby version 2 standby 10 ip 172.16.0.1 standby 10 preempt delay minimum 20 reload 20 sync 10 standby 10 name R1A+R3P standby 10 track 1 standby 10 track ATM0 hold-queue 100 out !

interface ATM0/0 description ADSL bandwidth 512 bandwidth receive 7000 no ip address no ip redirects no ip proxy-arp atm ilmi-keepalive dsl operating-mode auto ! interface ATM0/0.1 point-to-point ip address 89.186.xx.xx 255.255.255.252 ip access-group 100 in no ip redirects no ip proxy-arp ip nat outside ip virtual-reassembly pvc 8/35 encapsulation aal5snap ! !

How should I configure an external adsl modem?

Thank you

Reply to
Elia S.
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When I was still using the ADSL lines, I had them configured in "SIP Spoof" mode and connected to an ethernet interface (in fact on a VLAN via a VLAN-capable switch) with standard config for ethernet. Advantage is that you don't have any NAT in the modem.

It seems like it is becoming more and more difficult to obtain an ADSL modem that is just a modem, no builtin NAT router. (although it is good that you don't use PPPoA, this makes everything much worse but unfortunately is used by most local ISPs here)

What type of modem do you use?

Reply to
Rob

Meanwhile, at the comp.dcom.sys.cisco Job Justification Hearings, Rob chose the tried and tested strategy of:

I've never heard of SIP spoof mode, but one thing you can do when you've only got one routable IP but more than one device, is get a router that supports (half-)bridge [there doesn't seem to be much standardisation here] mode. The routable IP from the DSL gets assigned to a device on the LAN somehow, and if you're lucky you can still manage your router via a secondary private IP, and no-one's any the wiser until you tell them on Usenet. It's what I'm doing here with a Thomson [now 'Technicolor'] ST780WL and one public IP.

Reply to
alexd

version 12.3 service timestamps debug datetime msec service timestamps log datetime msec no service password-encryption ! hostname router ! boot-start-marker boot-end-marker ! enable password xxxxxxxx ! no aaa new-model ! resource policy ! no network-clock-participate slot 1 no network-clock-participate wic 0 ip subnet-zero ip cef ! ! no ip dhcp use vrf connected ! ! ip name-server 216.xxx.xx.xxx (provided by telco) ip name-server 216.xxx.xx.yyy (provided by telco) ! ! ! ! Internet FastEthernet0/0 ip address 10.XX.XX.xx 255.0.0.0 (private network) ip nat inside duplex auto speed auto ! interface Serial 0/0 ip address 216.XXX.XX.XX 255.255.255.252 (provided by telco- customer ip) ip nat outside encapsulation ppp no fair-queue no dce-terminal-timing-enable service-module t1 timeslots 1-24 service-module t1 remote-alarm-enable ! ip classless ip route 0.0.0.0 0.0.0.0 216.xxx.xx.xx ! ip http server ! access-list 1 permit any ! ip classless ip route 0.0.0.0 0.0.0.0 216.XXX.xx.xx The 216 ip provided by telco- telco ip) ! ip http server ! access-list 1 permit any ! control-plane ! ! line con 0 line aux 0 line vty 0 4 password xxxxxxx login ! ! end

Reply to
David

Hello Rob. I have abandoned this project because I will add an additional point of failure, in the ext modem.

I could use standard eth adsl modem as the alcatel speedtouch 570 or similar

"Rob" ha scritto nel messaggio news: snipped-for-privacy@xs8.xsall.nl...

Elia S. wrote:

When I was still using the ADSL lines, I had them configured in "SIP Spoof" mode and connected to an ethernet interface (in fact on a VLAN via a VLAN-capable switch) with standard config for ethernet. Advantage is that you don't have any NAT in the modem.

It seems like it is becoming more and more difficult to obtain an ADSL modem that is just a modem, no builtin NAT router. (although it is good that you don't use PPPoA, this makes everything much worse but unfortunately is used by most local ISPs here)

What type of modem do you use?

Reply to
Elia S.

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