L2TP from Customers to AAISP

There are two reasons to use L2TP to connect in to AAISP:

1. As a backup for your existing AAISP circuit in the event of a fault.
   • Logging in over L2TP using your DSL credentials (ie xxx@a.1) from a different ISP will give you your normal IP addresses. You can use this whilst your AAISP connection is being fixed.
   • This is enabled by default and available to everyone, there are no extra charges. Usage is taken from your quota in the usual way as if you were connecting over DSL.
   • Speed & monthly usage are capped depending on the service you have, but these should be reasonable for most users - see the main website as it'll be described there.
   • Regarding IP routing, The L2TP has priority over the DSL, so you'd want to bring it up/down as and when required as the DSL won't have IPs routed to it when the L2TP is up.
2. Connect in to AAISP over a third-party internet connection.
   • This gives you your an AAISP IPv4 address and an IPv6 block. This will then give you unfiltered internet access with public IP addresses etc.
   • Speed is capped at 200Mb/s (3Mb/s for the low-cost Light service).
   • There are more reasons for doing this and further information and ordering on A&A L2TP service.

Connection Details

• Endpoint:
  • l2tp.aa.net.uk
  • or l2tp6.aa.net.uk
• Username & Password as supplied
• Hostname: AAISP
• Authentication Protocol: CHAP/MSCHAPv2 or PAP, but recommend CHAP, as L2TP is not encrypted
• Plain L2TP without any IPsec. This is important as some devices may not support disabling encryption on L2TP, eg iPhones
• Check that your ISP/mobile provider does not have features that will block 'VPN' services - eg Vodafone's 'SecureNet' will block access to our L2TP service but can usually be disabled via the provider's control pages/App/etc
• Please use the DNS name (l2tp.aa.net.uk) instead of hardcoding an IP address; IP addresses can and do change. If you have to use an IP, use 194.4.172.12, but do check the DNS for l2tp.aa.net.uk in case it changes.
• Static routes? Some L2TP client's config needs to have a static route to route traffic to the L2TP server directly rather than through the tunnel(!) - in these cases you may need to add multiple static routes and keep them updated as the IPs that l2tp.aa.net.uk may change and increase over time.

Speed/Latency Tweaks

See: L2TP-Latency-Speed-Tweaks

MTU

You may have to set a lower MTU to accommodate the host ISP, possibly as low as 1462 (or lower for some ISPs and still lower for mobile networks). In theory fragments will work to allow 1500 MTU on our service, but fragments are inefficient, and if everyone sends fragmented packets that could degrade the service.

Port forwarding on some 'Mobile Broadband' routers

We have reports from a few customers who are using 4G/5G mobile data routers for 'mobile broadband' that whilst they do support L2TP they do not appear to port forward the static IP on the L2TP. The web UI suggests that port-forwarding can be configured, but this seems to only port-forward the IP address on the mobile data connection and not the IP address on the L2TP connection. We suggest that customers should report this as a bug to the supplier/manufacturer of the router. This can have an impact on using our L2TP service as these routers will be restricting the capabilities (ie port forwarding). A work-around is to to a separate Ethernet router on your LAN to establish the tunnel.

Notes on setting up L2TP IN to AAISP:

L2TP from FireBrick

Creating a L2TP connection from a FireBrick to AAISP

L2TP from OSX

Creating a L2TP connection from Apple OSX to AAISP

L2TP from iOS

Our L2TP service won't work from iOS (iPhones & iPads)

L2TP from Windows

Creating a L2TP connection from Windows to AAISP

L2TP from Debian

Creating a L2TP connection from Debian to AAISP using xl2tpd

L2TP from Linux

Creating a L2TP connection from Linux/Ubuntu/Network Manager to AAISP using xl2tpd

L2TP Failover with Debian

Creating a L2TP fallback for AAISP using xl2tpd

L2TP from Routerboard

Creating a L2TP connection from Routerboard to AAISP

L2TP from OpenWRT

Creating a L2TP connection from OpenWRT to AAISP

L2TP from Cisco

Creating a L2TP connection from Cisco to AAISP

L2TP from a SNOM VoIP Phone

Creating a L2TP connection from a SNOM phone to AAISP

L2TP from 4G/5G Huawei/Gigacube

Creating a L2TP connection 4G/5G Huawei/Gigacube type mobile broadband routers to AAISP

L2TP from Other Routers

Generic information for creating a L2TP connection from other routers to AAISP (eg Netgear, TP-Link etc that are not listed here

Ubiquiti

Problems with Ubiquiti Edgerouter

MikroTik

Create an L2TP connection from a MikroTik Routerboard

OpenWRT-Policy Based Routing

Create an L2TP connection from a OpenWRT with Policy Based Routing