Functions of the broadband access server in the whole network access service

There are many things worth learning about broadband access servers. Here we mainly introduce the functions of broadband access servers in the whole network access business. The broadband access server is mainly used to meet the current requirements of various DSL access applications, especially the application requirements of ADSL access networks. Currently, ADSL access is based on the ATM network platform, and is an ATM. However, the current network architecture is mostly pure IP and large. At the same time, the debate on ATM technology remains the focus of discussion in the industry.

The further expansion of the ATM network is difficult, and it is of practical significance to achieve the requirement of ADSL direct IP Access. On the other hand, with the increasing integration of access devices on the Access side, a connected network unit, such as DSLAM, can often be connected to hundreds of users. For such a network distribution and so many single-point connected users, it is also an ideal choice to switch the Broadband Access Server from centralized access to decentralized access. It can even be directly integrated with edge access devices on the Access side to integrate IP addresses directly connected to the network. This networking scheme is not only conducive to simplifying the Broadband Access Server's own equipment, but also easy to implement user QoS, and directly aggregates the accessed user data IP into the edge router, it is easy to integrate with existing IP networks and saves network transmission devices and channels on the network access side and edge side. It should be said that such Broadband Access Servers are cheap and easy to design, and are often bundled for direct use as part of the access device. However, the function is relatively simple, and the network scalability and scalability are poor. Using this networking solution is feasible for accessing a single network with a single business, but it cannot be used for complex business networks. From the current actual business orientation, high-speed Internet access has become the mainstream service for broadband access networks, with a single business type and few additional services, in this situation, decentralized access has some advantages.

From the perspective of the whole network, the broadband access server is not only a single aggregation point for the whole network access service, but also a unified forwarding point for the user's business traffic. In this special network point, if it can implement joint networking applications with other dedicated network devices, it can greatly improve the overall network performance and the actual access speed of users. As you can imagine, for Internet services, the Broadband Access Server is directly attached to a dedicated Cache and a layer-4 switch. In this way, information frequently accessed by users can be obtained directly from the dedicated Cache through layer-4 switch filtering, thus bypassing a large number of user data streams, it reduces many repetitive and unnecessary network traffic, greatly reduces the backbone network load, improves the network utilization, and has high application value. The performance improvement of the Broadband Access Server focuses on the access processing capability, switching capacity, and interface bandwidth and density. The system performance requirements for the next generation of large Broadband Access Servers are as follows:

① The switching capacity should be at least 40 GB;

② The number of PPP calls supported at the same time reaches 20 k;

③ The number of configurable users reaches 100 k;

④ The forwarding capability of an independent package is greater than 1 Mbit/s.

The Development Trend of IP addresses indicates that the introduction of Multi-Protocol Label Switching MPLS can smoothly upgrade the network, making it easy to implement IP service quality assurance and VPN applications. These applications have incomparable advantages over other technologies. MPLS has become the industry's consensus on the development direction of next-generation IP addresses, and support for broadband access servers is an inevitable choice.