FTTC config in the UK on 887 routers etc

[carl.townshend]

Hi All

We have always had ADSL on most of our routers using the ATM 0 interface and a dialler with PPPOA.

We have recently moved one of them to FTTC, still using the RJ11 cable on the back of the router.

We ended up using the dialler interface and an sub interface like the below

bba-group pppoe global
!
!
interface ATM0
no ip address
shutdown
no atm ilmi-keepalive
!
interface Ethernet0
no ip address
!
interface Ethernet0.101
encapsulation dot1Q 101
pppoe enable group global
pppoe-client dial-pool-number 1

interface dialler 1
mtu 1492
ip address negotiated
ip access-group Access-In in
ip nat outside
ip inspect firewall out
ip virtual-reassembly in
encapsulation ppp
dialer pool 1
dialer-group 1
no cdp enable
ppp authentication chap callin optional
ppp chap hostname ****
ppp chap password 7 ****

How come we dont use the ATM0 interface anymore even though the RJ11 cable is plugged in?

Is this now using PPPOE?

Why does it use vlan 101, is this standard for FTTC?

[pieterh]

>>> We have recently moved one of them to FTTC, still using the RJ11 cable on the back of the router <<<
this is probably not correct you are NOT using the RJ11 cable. it may be plugged in, but will not be operational,
it is replaced with the interface Ethernet0 connection (RJ-45 , not RJ11) and PPPoE (E=Ethernet)

>>> Why does it use vlan 101, is this standard for FTTC? <<<
not necessarily.
1) your ISP can transport multiple customers over the same fiber,
    each separated by using it's own VLAN
2) or ..... you can have multiple connections to your provider, with each having it's own vlan
e.g. an internet connection using vlan 101, and multiple point-to-point link to a branch office using vlan 102, 103 etc.
your provider determines which vlan is used for which customer or service

[carl.townshend]

Hi Pieterh

The RJ11 is plugged in to the socket on the wall which provides the broadband, the fast ethernet is plugged into the LAN side.

We have shut down the ATM0 interface and it still works, so I wonder if it uses the RJ11 as an ethernet pass through perhaps ?

Cheers

[paul driver]

Hello

---

@carl.townshend wrote:

We have recently moved one of them to FTTC, still using the RJ11 cable on the back of the router.

---

Sounds like you do not need it, the cable omitting from  Ethernet0 is now active PPoe physical interface

[carl.townshend]

Hi Paul

When you say cable emitting from ethernet 0, there is no "physical" ethernet 0, the ISP cable is plugged into the VDSL over POTS port, are we saying that this is actually also the ethernet 0 port ?

[paul driver]

Hello
What rtr are you using

[carl.townshend]

Cisco 887VA

[pieterh]

again this response does not match your statement: >>> We have recently moved one of them to FTTC <<<
FTTC means Fiber To The Cabinet
as such your provider runs a fiber-cable to your equipment room, where it needs a CPE to terminate the fiber cable 
and from the CPE a cable runs to your equipment, normally this is ethernet, but is can also be a different connection (DSL, ISDN)

if above CPE is not present, I think you did not migrate to FTTC

take a look at this post Cisco 887 ethernet interfaces - Cisco Community
that says: Ethernet0 is a virtual interface that is used for VDSL configuration.

Ref: http://www.cisco.com/en/US/docs/routers/access/800/860-880-890/software/configuration/guide/routconf.html#wp1163169

HTH,

[carl.townshend]

Hi, FTTC in the UK means fiber to the cabinet, the cabinet is in the street and they then run copper cable to to premises, you are getting mixed up with FTTP which is fiber to the premises

[pieterh]

thank you for this explanation

[pieterh]

Cisco 887VA	Multimode VDSL2/ADSL2/2+ over basic telephone service	4-port 10-/100-Mbps managed switch	Yes (Cisco 887VAW)	Yes (Cisco 887VAG)	No
C887VAM	Multimode VDSL/ADSL Annex-M over POTS	4-port 10-/100-Mbps managed switch	No	No	No
Cisco 887	ADSL2/2+ over basic telephone service (Annex A)	4-port 10-/100-Mbps managed switch	Yes (Cisco 887W)	Yes (Cisco 887G)	Yes
Cisco 887V	VDSL2 over basic telephone service	4-port 10-/100-Mbps managed switch	Yes (Cisco 887V)	Yes (Cisco 887VG)	Yes

Step 1	controller dsl slot/port Example: Router(config)# controller dsl 0	Enters controller configuration mode and the controller number.
Step 2	mode atm Example: Router(config-ctrl)# mode atm	Enables ATM encapsulation and creates logical ATM interface 0.

conclusion the RJ-11 connection is ADSL or VDSL to the cabinet in the street
the ATM interface is  a logical interface created by setting mode of controller dsl 0
the ethernet0 interface is also a logical interface created when setting the mode of controller dsl 0