Load balancing of multi-wan routers viewed from application requirements

ADSL, such as broadband access because of its economic and adequate, that is, cost-effective advantages of many small and medium-sized enterprises favored. With the development of enterprise business, especially for some medium-sized enterprises and enterprises with high dependence on network, they will consider bandwidth expansion or planning large bandwidth access. Multi-line broadband access is often its first choice, there will be some enterprises will choose "optical fiber +ADSL" and other modes, regardless of the type of access, enterprise users from the cost of ownership, operational cost perspective, most of the choice of multiple WAN port router for its use.

However, in the procurement of multiple WAN port routers, what function of the product to meet their own needs, almost every network device managers are puzzled by the problem. After communication with the first-line sales engineers, the author summarizes the problems that customers often encounter: the requirement and function matching is the standard.

The load balancing function and the applicable object of the multiple WAN port router which are common to the market are explained for reference.

No load balancing: not suitable for any one user

When early multi-WAN router products are on the market, some vendors directly modify the hardware functionality on a single WAN router, which becomes a dual-wan router. These routers do not make much changes to the software, but simply apply the need for the Internet to different WAN ports. That is, routers do not judge, arbitrarily assign user requirements to simple principles, such as randomly allocating to different WAN ports or at different times to different WAN ports. From the practical experience, it is found that the load balance often occurs one line congestion, while the other is idle, the bandwidth is not well utilized.

These products can only be described as routers with multiple WAN port hardware, but do not have load balancing capabilities and are not capable of maximizing the benefits of multiple WANs. As a matter of fact, there are some cheaper dual-wan routers that are still using this design. On the whole, this kind of router not only helps the user not to be helpful, but may waste the user the broadband line the expense, does not suggest the user buys this kind of design the router product. Users should be careful not to purchase this product.

Simple load balancing: For single operator multiple line users

Multi-Wan router products are derived from abroad, mainly as a function of bandwidth expansion or redundancy, so load balancing functions mainly consider how to average the bandwidth to different WAN ports. Common distribution methods can be divided according to the intranet IP distribution, according to the number of online distribution, according to the proportion of bandwidth users to distribute the Internet needs. According to the Internet IP distribution according to the order of the network, the different users are assigned to the different WAN port in turn, in order to balance the flow, according to the online number is the customer's online requirements, allocated to different WAN, bandwidth usage is based on the bandwidth usage of different WAN, in order to allocate a new network packet, so as to avoid a line congestion, First-line idle situation.

These distribution methods are recognized in foreign applications, because there is no bottleneck between the different carriers in the foreign countries, and the response speed is similar to those distributed to different WAN ports. In the domestic situation, due to the lack of bandwidth between the network of different telecom operators, it will cause some problems. When the user requests the service of the telecommunication server, if the router transfers to the Netcom line, the response will be slower. That is to say, for the Internet café or enterprise user who intends to apply for multiple lines of the same carrier, this load balancing router is applicable.