Multipath TCP is Likely Included in Apple's iOS 7

Multipath TCP is a TCP extension, networking protocol that lets a connection send or receive packets over different interfaces. There was some exciting news in recent days after it was reported the protocol is believed to be included in Apple's iOS 7, which was released on Wednesday.

The step represents “the first large scale commercial deployment of Multipath TCP,” according to Olivier Bonaventure, a computer science professor at the IP Networking Lab in Belgium, who was the first one to identify Apple’s use of MPTCP (MultiPath TCP).

“Given the marketing buzz around new iOS7 releases, we can expect tens of millions of users who will use a Multipath TCP enabled device,” he adds in a blog post. “Packet traces collected on an iPad running iOS7 reveal that it uses Multipath TCP to reach some destinations that seem to be directly controlled by Apple. You won’t see Multipath TCP for regular TCP connections from applications like Safari, but if you use SIRI (a cloud-based voice command and navigation service), you might see that the connection with one of the Apple servers runs…(using) Multipath TCP.”

Some of its uses include letting smartphones use Wi-Fi and 3G interfaces at the same time or if be used if there is a failover. This is a likely iPhone use.

The new protocol could also improve TCP performance in data centers. Or, it can improve performance on dual stack hosts running IPv4 and IPv6.

It took five years of hard work before the IETF published Multipath TCP as a specification in January. It was then called an “experimental standard.” In July there were three independent implementations of Multipath TCP.

“One of Multipath TCP's benefits over traditional TCP extensions is the protocol's ability to push data through the most efficient network, which leads to fewer dropouts. If one channel fails, another will take over,” Apple Insider said.

Looking at the bigger picture, Multipath TCP is part of an “effort to transform the Internet from a mainly data network today to one that supports far more demanding applications such as telephony and IP TV,” Network World adds.

So the recent news is a major step in the history of the promising protocol.