BTInfinty connection using a Cisco 887a router

On your # sh ip int brief output everything is down ... protocol down means - it is down :).

Interface         IP-Address   OK?   Method Status Protocol

ATM0               unassigned YES   NVRAM down down
Dialer1             unassigned YES   NVRAM up up
Ethernet0        unassigned YES   NVRAM administratively down down
FastEthernet0 unassigned YES   unset up down
FastEthernet1 unassigned YES   unset up down
FastEthernet2 unassigned YES   unset up down
FastEthernet3 unassigned YES   unset up down
NVI0                 unassigned YES    unset administratively down down
Vlan1               192.168.0.1 YES    NVRAM up down

What you are missing for sure is default route
ip route 0.0.0.0 0.0.0.0 dialer1

access-list 10 permit 192.168.0.0 0.0.0.255
access-list 10 remark nat-pool
access-list 23 permit 192.168.0.0 0.0.0.255
access-list 23 remark vty
access-list 23 deny any log

There is no need to have it written two times (you can use just one if you want).

access-list 10 permit 192.168.0.0 0.0.0.255
access-list 10 remark nat-pool

is equal to (except log part)

access-list 23 permit 192.168.0.0 0.0.0.255
access-list 23 remark vty
access-list 23 deny any log

Typical ATM configuration looks similar to (provider dependent)

interface ATM0
 no ip address
 no atm ilmi-keepalive
 pvc 8/35
 tx-ring-limit 3
 encapsulation aal5mux ppp dialer
 dialer pool-member 1

Hi, thank you so much for your reply.
I am having difficulty bringing the interfaces up. If I do a "no shutdown" on ATM0 I get:

ATM0 is initializing, line protocol is down
  Hardware is MPC ATMSAR, address is 0007.7deb.c0fa (bia 0007.7deb.c0fa)
  MTU 1520 bytes, sub MTU 1520, BW 4608 Kbit/sec, DLY 80 usec,
     reliability 255/255, txload 1/255, rxload 1/255
  Encapsulation ATM, loopback not set
  Keepalive not supported
  Encapsulation(s): AAL5
  4 maximum active VCs, 1024 VCs per VP, 0 current VCCs
  VC Auto Creation Disabled.
  VC idle disconnect time: 300 seconds
  Last input never, output never, output hang never
  Last clearing of "show interface" counters never
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
  Queueing strategy: Per VC Queueing
  5 minute input rate 0 bits/sec, 0 packets/sec
  5 minute output rate 0 bits/sec, 0 packets/sec
     0 packets input, 0 bytes, 0 no buffer
     Received 0 broadcasts (0 IP multicasts)
     0 runts, 0 giants, 0 throttles
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
     0 packets output, 0 bytes, 0 underruns
     0 output errors, 0 collisions, 0 interface resets
     0 unknown protocol drops
     0 output buffer failures, 0 output buffers swapped out

It will stay like this for a while and then stop trying and revert back to "Status - down".

I fear I am making more of a mess of this.  I think I have incorporated your suggestions but I know I need to delete some of the points that you made, like the duplicated access list lines. Can you tell me how to do this?

So, this is my current config now:

Using 3443 out of 262136 bytes
!
! Last configuration change at 16:44:53 BST Tue Sep 20 2016 by administrator
!
version 15.1
no service pad
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
service internal
!
hostname rtr-h003103
!
boot-start-marker
boot-end-marker
!
!
logging buffered 4096
enable secret 5 $1$ADmv$NWsaGiCyPI/apxJCnTNqG1
enable password $1$ADmv$NWsaGiCyPI/apxJCnTNqG1
!
aaa new-model
!
!
aaa authentication login default local
aaa authentication enable default enable
aaa authorization exec default local
!
!
!
!
!
aaa session-id common
memory-size iomem 10
clock timezone gmt 0 0
clock summer-time BST recurring last Sun Mar 2:00 last Sun Oct 3:00
crypto pki token default removal timeout 0
!
!
no ip source-route
!
!
!
ip dhcp excluded-address 192.168.0.0 192.168.0.99
ip dhcp excluded-address 192.168.0.200 192.168.0.254
!
ip dhcp pool 10
   import all
   network 192.168.0.0 255.255.255.0
   dns-server 8.8.8.8 4.2.2.2
   default-router 192.168.0.1
!
!
ip cef
ip name-server 8.8.8.8
ip name-server 4.2.2.2
ip inspect WAAS flush-timeout 10
no ipv6 cef
!
!
license udi pid CISCO887VA-K9 sn FCZ1524C3GD
!
!
username admin privilege 15 secret 5 $1$iFs5$Gc3bZQfrlbBbWHQ7DvTE3/
username user privilege 15 secret 5 $1$yAV0$dUswDZwNZLZXk9jBysqfY0
!
!
!
!
controller VDSL 0
 operating mode ansi
 modem customUKAnnexM
 modem customUKAnnexA
 modem UKfeature
!
ip ssh version 2
!
!
!
!
!
!
bba-group pppoe global
!
!
interface Ethernet0
 no ip address
 shutdown
 pppoe-client dial-pool-number 1
!
interface ATM0
 no ip address
no atm ilmi-keepalive
 pvc 8/35
  encapsulation aal5mux ppp dialer
  dialer pool-member 1
 !
!
interface FastEthernet0
 description Uplink to fw-h003104
 speed 100
!
interface FastEthernet1
!
interface FastEthernet2
!
interface FastEthernet3
!
interface Vlan1
 ip address 192.168.0.1 255.255.255.0
 ip nat inside
 no ip virtual-reassembly in
 ip tcp adjust-mss 1452
!
interface Dialer0 (**I need to delete this interface I think**)
 ip address 81.x.x.x 255.255.255.254
 shutdown
!
interface Dialer1
 description BTInfinity
 mtu 1492
 ip address 81.x.x.x 255.255.255.254 (**Some people say not to enter the static IP but I'm not sure**)
 no ip redirects
 no ip unreachables
 no ip proxy-arp
 ip nat outside
 no ip virtual-reassembly in
 encapsulation ppp
 dialer pool 1
 dialer idle-timeout 0
 dialer-group 1
 ppp authentication chap pap callin
 ppp chap hostname username@xx.btclick.com
 ppp chap password 0 mypassword
 ppp pap sent-username username@xx.btclick.com password 0 mypassword
 ppp ipcp dns request accept
 ppp ipcp route default
 ppp ipcp address accept
no cdp enable
!
ip forward-protocol nd
no ip http server
no ip http secure-server
!
ip dns server
ip nat inside source list 10 interface Dialer1 overload
ip route 0.0.0.0 0.0.0.0 Dialer1
ip route 0.0.0.0 0.0.0.0 192.168.0.100 (**Maybe I need to delete this line after entering the line above?**)
!
logging esm config
access-list 10 permit 192.168.0.0 0.0.0.255
access-list 10 remark nat-pool
access-list 10 remark nat-pool (**How do I delete these 3 lines?**)
access-list 23 permit 192.168.0.0 0.0.0.255
access-list 23 remark vty
access-list 23 deny   any log
dialer-list 1 protocol ip permit
!
!
!
!
!
!
control-plane
!
banner login ^CCC
THIS IS A PRIVATE SYSTEM. UNAUTHORISED ACCESS IS NOT
PERMITTED AND OFFENDERS ARE LIABLE TO PROSECUTION.

YOUR IP HAS BEEN LOGGED AND AN ALERT GENERATED
^C
!
line con 0
 privilege level 15
 logging synchronous
 no modem enable
line aux 0
line vty 0 4
 access-class 23 in
 ipv6 access-class ipv6_deny in
 transport input telnet
 escape-character 3
!
scheduler max-task-time 5000
end

I really appreciate your time and any further suggestions you can make.
Becky

Hi Becky,

The Infinity service uses the Ethernet interface for VDSL.  The ATM interface is for ADSL.

This is what you need...

https://community.bt.com/t5/Connected-Devices-Other/BT-infinity-with-a-Cisco-router/td-p/407209/page/2

FYI, BT Infinity doesn't support static IP addresses on its residential service.

Typically (not always) you can delete commands by using keyword no and then command

no interface Dialer0
no ip route 0.0.0.0 0.0.0.0 192.168.0.100
no access-list 23

interface Dialer1
 no ip address
 ip address negotiated

line vty 0 4
 no access-class 23 in
 access-class 10 in

Thank you for feedback it could be useful (never had contact with BTInfinity so far, although I do not expect that I will have it, but who knows) but, according to solution missing default route in your configuration was not problem at all, also having almost the same configuration details on link provided by Craig Beck is close to solution.

interface ATM0
 no ip address
 shutdown
 no atm ilmi-keepalive

interface Ethernet0.101
description Tagging for PPPoE (VDSL 0)
encapsulation dot1Q 101
ip nat outside
ip virtual-reassembly in
no ip route-cache
pppoe enable group global
pppoe-client dial-pool-number 1

interface Dialer1
description **BT INFINITY**
ip address negotiated
ip access-group 101 in
no ip redirects
no ip unreachables
no ip proxy-arp
ip mtu 1492
ip nbar protocol-discovery
ip flow ingress
ip nat outside
ip virtual-reassembly in
encapsulation ppp
ip tcp adjust-mss 1452
dialer pool 1
dialer-group 1
ppp authentication pap chap ms-chap callin
ppp chap hostname *-*
ppp chap password 0 password
ppp ipcp dns request accept
ppp ipcp route default
ppp ipcp address accept
no cdp enable

I did not read full path to solution on link, but I guess it is there (having subinterface 0.101 marked as ip nat outside and dialer1 marked the same way does not look good in start configuration on link)...
;)

Cheers for the update, Becky.

You don't specifically have to use the encapsulated VLAN on the Infinity service unless you want to use the BT YouView multicast service for TV (which doesn't work with btclick accounts IIRC).  Internet traffic will work fine even if it's not encapsulated.

The guide found on YouTube resolved my issue.