Bandwidth Bonding Example

In the following example bearer bonding is achieved when a mobile user is connected to Net A and moves into the coverage area of Net B. A policy has been established that instructs the Apollo Anywhere Client to bond Net B with Net A and, after having tested the end-to-end connection to the PAS over Net B, the Anywhere Client establishes a data connection over it and bonds it to NET A while maintaining the integrity of the end-to-end session. Apollo maintains the IP address allocated to the Windows IP stack transparently to the 2 wide area network IPs allocated to the two network interfaces.

Figure 5 How bonding over 2 dissimilar networks works using Apollo

This example assumes that the Apollo Anywhere Client on the mobile device has been instructed to connect to the Apollo PAS and is now continually monitoring two separate NICs or modems for coverage.

1. Anywhere Client identifies Net A coverage, tests the end to end connection to the PAS, reports the performance and connects.
2. Anywhere Client identifies Net A coverage and Net B coverage, test the end to end connection to the PAS over Net B, reports the performance and adds the Net B bandwidth to the Net A bandwidth.
3. Anywhere Client identifies loss of Net A coverage and continues connectivity on Net B only.
4. Anywhere Client identifies Net A coverage and adds the Net A bandwidth to the Net B bandwidth.
5. Anywhere Client identifies loss of Net B coverage and continues connectivity on Net A only.
6. Anywhere Client identifies loss of Net A coverage and suspends data session. During this time both Anywhere Client and PAS maintain session context and keep applications “alive” on both ends.
7. Anywhere Client identifies Net A coverage and resumes data session with PAS.

Apollo is able to fragment packets making it possible to split a single packet down multiple channels. This helps to reduce the effective overall round trip time by significantly reducing the serialization delay. Apollo’s channel bonding is superior in its flexibility when compared to the traditional link layer bonding used previously on fixed timeslot ISDN networks and can combine different bandwidth / latency / metrics sources / bearers into a single aggregated pipe.