Direct private peering is, as the name suggests, is a direct private connection between BT’s Internet platform and a Cloud service provider.

This is achieved through either an in-building connection at an IXP or a via a crosstown circuit. BT commonly uses direct private peering where there are higher traffic levels and demand. With private peering we exclusively send and receive data too and from Cloud service providers via dedicated ports, which means the traffic can be handled directly with the cloud provider and without the need to route over the public internet. This allows us to prevent congestion and packet loss across the connection while helping to minimise latency.

BT's extensive peering arrangements are a critical component to providing outstanding connectivity and performance for our customers as well as increased service resilience through diversified routing. Peering is the bedrock of our network and we actively expand our peering capacity in line with traffic growth to maintain world class performance.

BT's Internet network capability consists of BT's European Backbone (AS5400), the UK (AS2856), plus in-country Internet networks in Ireland, Italy and Spain. BT also has Internet networks in Latin America and the Global Infonet Internet Backbone (AS3300).

BT has a selective peering policy

We select our peers based on their performance, capability and where our traffic needs to go. Our choice of peering partner can have a direct effect on our customers, and we understand that this demands very high performance from our peering partners as well as from ourselves.

Much of our customer’s traffic is domestic: we aim to maximise this where possible to minimise latency. Our international traffic also benefits from our depth of reach throughout Europe at all the major European IXPs (Internet Exchange Points) and from our connectivity to US networks via IXPs in the USA.

BT is a European Tier 1 provider and has connections to US and Global Tier 1 networks. BT’s Internet network outside the UK runs over our wholly owned 55,000 km fibre network and part-owned transatlantic cables.

BTnet delivers excellent performance across our own network, with weekly performance data such as network latency.

Our BTnet Service Level Agreement (SLA) also guarantees <20ms latency within the UK core network and <95ms via our Trans-Atlantic connection.

Our internet platform is present in major public ‘Internet Exchange Points’ (IXP) across the world,where most SaaS (Software as a Service) and IaaS (Internet as a Service) providers are located.

This allows us to offer excellent peering with these providers for common web applications and Cloud services. Peering allows exchange of traffic from our customers to the other Cloud service providers and platforms with high levels of service quality and low latency.

Our networks are present at the following data centers for public or private peering:

BTnet also uses transit peering where direct or public peering is not possible or required, due to where our Points of Presence (PoPs) are located and/or due to low volumes not allowing us to reach peering agreements. Transit peering is also used where traffic volumes don’t justify peering and typically used for less than 1G connections to the services via 3rd party transit. We connect using Global Tier 1 partners for maximum connectivity, but we also connect with local providers for good regional coverage.

BT uses either 3rd party transit, or in some cases uses BT as a transit provider for connecting to services that are directly connected elsewhere. Using transit peering allows us to get optimum connectivity for global internet end points even where traffic demands are low or we have no direct peering relationship.

With public peering and 3rd party transit, we receive traffic from and send traffic to multiple services on the same ports. Additionally, Cloud service providers are likely sending traffic to and receiving traffic from multiple ISPs on the same ports. Packet loss and buffering over the interconnect is therefore more likely than it would be with direct peering, however we and our partners work hard to prevent this from happening.

Note that where traffic is between two BTnet customer sites, the traffic will remain ‘on-net’ for optimum performance and will not need to use 3rd party transit.

Terms and conditions All information within this page is for illustrative purposes only and may be subject to change without notice. Peering partners will also be updated over time.

This is achieved using a shared port at an IXP allowing the exchange of traffic from our customers to multiple peering partners’ customers. Public peering is used typically for traffic volumes less than 10G, and sometime as resilience for some smaller private peers. Multiple peers are connected over IXP (Internet exchange points) Layer2 fabric.

Assuming locations for peering are the same there should be minimal difference in performance or security for our customers compared with private peering. Public peering is using shared infrastructure so in theory there is the potential for contention but in practice port size and IXP infrastructure is managed to avoid this as much as possible.