多条CE1捆绑成一条4M的链路，做负载均衡

可以用路由来解决, 简单的静态和动态都可以，也可以买E1复用器；第二层一定要捆绑的话只有用ppp, 对端的routerB可以一样对称配置
hostname RouterA

username RouterB password abc

ip subnet-zero

multilink virtual-template 1

!

< P>interface Virtual-Template1

ip unnumbered Ethernet0

ppp authentication chap

ppp multilink

!

interface Serial0

no ip address

encapsulation ppp

no fair-queue

ppp multilink

pulse-time 3

!
interface Serial1

no ip address

encapsulation ppp

no fair-queue

ppp multilink

pulse-time 3

通过此方法，我们可将多条低带宽线路合并成为一条线路，并通过虚拟端口Virtual-Template 1进行数据的传输。按此方法配置完成后，我们会发现在显示端口状态（sh interface）时，凭空多出一个端口Virtual-Access 1，此端口的数据流量恰恰等于各实际端口的流量总和，并且通过它将数据流量均分到各个实际端口当中去。从而达到合并低带宽线路的目的。

此外，在配置此功能时，需要注意以下几点：

1． 此功能只能封装PPP协议。
2． 在interface virtual-template 1配置中，ip unnumbered Ethernet0可用ip address XXX(地址)来取代。
3 .ce1物理配置自己添上就行了, 我看最好把所有信道都捆起来作成e1来用

附：Bundling NxE1 Links With a Multilink Interface

Contents

     
     
     
     

     
     


     
     

The sample configurations in this document show how NxE1 links (with or without G.704 framing) can be bundled by means of a Multilink interface. The Multilink interface is introduced in Cisco IOS® Software Release 12.0(3)T for distributed Multilink Point to Point Protocol (PPP) on Cisco 7500 router Versatile Interface Processor (VIP)-based T1 or E1 interfaces (see below). It is supported for non-VIP based T1/E1 (and other WAN) interfaces since Cisco IOS Software Release 12.0(4)T.

For more information on document conventions, see the .

Since Multilink PPP increases the CPU load, you are advised to:

1. Verify the current average CPU load before adding Multilink interfaces or adding E1 links to a Multilink interface.

2. Use distributed Multilink PPP on Cisco 7500 VIP-based platforms whenever possible. For more details on the restrictions and prerequisites of distributed Multilink PPP, please refer to the Cisco IOS Software Release 12.0(3)T New Feature Documenation (see below).

3. Disable Multilink PPP fragmentation whenever possible.

Note: This increases latency over the Multilink bundle.

The information in this document is based on the software and hardware versions below.

• A Cisco 7505 router equipped with VIP2-50 and PA-MC-8E1 and running Cisco IOS Software Release 12.1(11a).

• A Cisco 7206 router equipped with PA-MC-8E1 and running Cisco IOS Software Release 12.1(11).

The information presented in this document was created from devices in a specific lab environment. All of the devices used in this document started with a cleared (default) configuration. If you are working in a live network, ensure that you understand the potential impact of any command before using it.

Multilink PPP, standardized in Request for Comments (RFC) 1990, is similar to load balancing techniques in that it sends packets across the individual links in a round robin fashion. However, Multilink PPP adds three significant capabilities.

• Firstly, because multilane PPP works at the link layer, it makes an NxT1/E1 bundle appear as one logical link to the upper layer protocols in the router. Thus, only one network address needs to be configured for the entire NxT1/E1 bundle.

• Secondly, Multilink PPP keeps track of packet sequencing and buffers packets that arrive early. With this ability, Multilink PPP preserves packet order across the entire NxT1/E1 bundle.

• Thirdly, packet fragmentation can be enabled to split large data packets into smaller packet fragments that are individually transmitted across the links. In many circumstances, fragmentation can increase the efficiency of the NxT1/E1 link.

Multilink PPP also offers significant link manageability. If an individual link fails, Multilink PPP can automatically detect the failure and remove that link from the bundle. As long as one link of the bundle is working the logical interface representing the bundle is up. By using keep alive signals, Multilink PPP can detect when a previously failed link comes back up then reinsert that link into the bundle. Additionally, when more bandwidth is needed, additional links can be added to the bundle by simply configuring them as a member of the bundle. No reconfiguration at the network layer, such as new addressing, is needed. This is also a significant factor when considering the use of advanced router services. A specific quality of service, for example, can be configured once for the bundle as a whole rather than on each link in the bundle.

The trade-off for the increased functionality is that Multilink PPP requires greater CPU processing than load balancing solutions. Packet reordering, fragment reassembly, and the Multilink PPP protocol itself increases the CPU load.

For a detailed description and comparison of alternatives for high bandwidth connections using parallel E1 links, please refer to the .

In this section, you are presented with the information to configure the features described in this document.

Note: To find additional information on the commands used in this document, use the ( customers only) .

This document uses the network setup shown in the diagram below.