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Everything You Must Know About RTP Protocol

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Imagine setting up a video call for the most important investor meeting of the year and dealing with jitters, lag, and connectivity issues the whole time. In the best case scenario, you look unprofessional with your janky tech setup—and in the worst case scenario, the investors bail on you.

Your first move might be to assume your internet speed is too slow, but the truth is your systems may be out of date.

Real-time Transfer Protocol, or RTP, is the new standard for sending multimedia messages and making video calls. In fact, RTP is part of the technology that makes advanced communication solutions like Voice over Internet Protocol (VoIP) possible. But it also has a ton of other uses that businesses should know about.

Yes, in a conference call, RTP is the thing that stops the video from janking out—but in a broader sense, it represents many aspects of how modern businesses communicate.

Nextiva conference call landing page with a button to learn more.

RTP Enables Real-Time Communications

RTP was designed in the 80s, but today’s video conferencing software uses the more advanced, current version of it. VoIP is becoming the new standard for business phones, and calling people using an internet connection is really just an application of RTP.

In general terms, RTP works by translating multiple data types, like video and audio files, into a single transmission. It uses multiple “flows” of data so it can give itself feedback on how the data is being transported.

This is why RTP is able to solve some of the annoying problems with traditional connections, like dropped calls, fuzzy video feeds, and the dreaded lag. RTP’s ability to maintain multiple streams is also why calls over VoIP are usually clearer and more reliable than phone connections.

For businesses that are a little behind the times, upgrading to RTP-enabled systems can be like magic. But the protocol obviously isn’t magic—it’s the result of established technology finally gaining consumer viability in a business setting.

The way it works can seem complicated, but breaking it down into the following steps can help simplify the process:

  1. To prepare your multimedia message, RTP has to encode it by using what’s called a “codec.” This makes the message small enough to transport over an internet connection.
  2. After encoding, RTP splits the message into smaller parts known as packets. The size of these packets changes depending on what media is being sent. For example, making a video call requires smaller packets than those used for making voice calls on an internet-based phone app.
  3. Next, each data packet needs a header, which is a list of information that RTP gives itself so that it can keep all the data straight. This info includes things like a timestamp, the number of each packet in the overall sequence, the data type, and other technical details. This is all done automatically by RTP with no input required.
  4. Finally, once the packets have been split, labeled, and arranged, RTP sends the message over the internet using what’s called a transport protocol—which is basically another, even smaller protocol used by RTP to send the newly organized multimedia message.
  5. If all goes well, the receiver will get the packets and RTP will recreate the original video/audio data using the details it already attached to each one before sending. If the sequence is correct, the data received should be identical to the data sent.
  6. If the data doesn’t match exactly due to a bad connection or corrupted files, RTP will decide what to do based on its other protocols. It’s worth noting that it’s possible to prioritize efficiency or reliability when setting things up with your vendor.

To the end user, the technical side of how RTP enables real-time communication happens automatically and behind the scenes. As an ongoing call or session takes place, RTP keeps referencing its sequence to make sure everything is synchronized and displayed correctly based on the custom rules set by you and your VoIP vendor.

With an RTP-enabled system, the days of waiting five seconds to hear what someone on the other end of the line just said are long gone. But there are new responsibilities to keep in mind if you want the system to run smoothly.

RTP Runs On Top of Other Protocols

There are two smaller protocols that help RTP send the message once it’s done fiddling with it: UDP and TCP. It’s important to know which one you have enabled on your system because it makes a difference.

Actually, the two protocols essentially do the same thing, but since they prioritize different aspects of data transfers, they have different benefits and tradeoffs.

RTP via UDP

User Datagram Protocol (UDP) doesn’t check to make sure the data is in the right sequence before sending. Instead, it focuses on getting transmissions out fast.

UDP doesn’t have any “overhead” or the extra memory required to perform messaging tasks. As such, it is known as a connectionless protocol because it doesn’t check to make sure the other system is available to receive a message. To save time, UDP just packs it up and sends it as soon as it’s ready.

This makes UDP the fastest way to send multimedia data over conference calls, which is why it’s used for real-time streaming. Of course, this also makes UDP less reliable because it won’t check and retransmit any data packets that are faulty or missing. Instead, it just moves on and keeps sending the next items in the sequence.

RTP via TCP

Transmission Control Protocol (TCP) is the other option that businesses usually pick for their RTP systems. Unlike UDP, TCP is more methodical, prioritizing reliability at the expense of speed.

TCP does this by checking to make sure the receiving system acknowledges and verifies the data. If the other system takes too long, perhaps due to a corrupted transmission, the system that tried to send it will try again with a new transmission.

This makes TCP both more reliable and slower than UDP. For instance, communication timeouts can happen on TCP-enabled systems while the system tries to ensure the exactness of the data. This is why you rarely see a system using TCP to conduct video conferences or stream movies.

Instead, TCP is best used for file transfers and other important one-to-one communications where time isn’t as much of an issue.

At the end of the day, the system you choose for your business should depend on the goals of your communication. Keep in mind that your system provider can help you customize your setup for what you intend to do with it.

RTP Cooperates With Other Protocols

In addition to working with core transport protocols, RTP can be used with other large systems to enhance a business’s communication abilities. These other systems add features or adjust network conditions to customize RTP for specific needs.

Generally speaking, there are four main protocols that a business should prioritize when improving its RTP communication framework.

SIP: SIP stands for Session Initiation Protocol, which is like a call administrator that makes connections between two systems. It looks up the internet addresses of the phones or devices, figures out if the call will go through, and controls the RTP data stream. Like RTP, SIP makes systems like VoIP possible.

VoIP: Voice over Internet Protocol uses other systems like SIP and RTP to replace traditional phone lines for businesses. VoIP services allow businesses to make calls over simple internet connections instead of physical landlines, allowing for easier scalability and bigger savings. Many VoIP vendors allow businesses to keep their old phone numbers, too, ensuring that the switch between systems is seamless for customers.

RTSP: The Real-Time Streaming Protocol is how RTP streams can be paused and played. It’s essentially the same thing as RTP these days, so only old-school tech folks will talk about them separately. They’re technically two different protocols that should be enabled on your system.

RTCP: The Real-time Transport Control Protocol is a long name for an optional addition to RTP when used for VoIP. Simply put, RTCP helps administrators monitor business call quality by tracking certain features like jitter, delays, and data loss. It provides a good way of identifying any issues that are lowering your call quality.

Secure Real-Time Transport Protocol

The Secure Real-Time Transport Protocol (SRTP) is an extension of RTP that improves security for your business. The features it adds are especially useful for businesses that want to replace their landlines with VoIP.

SRTP comes with some optional but important benefits. Most prominently, it authenticates your data streams, meaning your business calls will always remain between you and your clients.

This doesn’t mean SRTP can encrypt messages, however, as it’s more of an authentication process. The system simply checks to make sure the network receiving the message is authorized to do so.

Still, now that more and more sensitive business communication is occurring over cloud-based servers using third-party systems, businesses are naturally more concerned about the safety of their corporate info. SRTP is really just a starting point for security, and you may have to enable it to minimize risk.

High-quality VoIP providers will usually have SRTP enabled on their systems, but you should always ask your vendor how they handle security—including the modifications it can make to RTP in order to keep your sensitive info safe. As easily as RTP can make your business more efficient, the wrong configuration could leave you vulnerable as well.

The Takeaway for Businesses

RTP provides a reliable protocol for businesses to take their communication into the 21st century. As more businesses switch from landlines to VoIP systems, the competition for clearer, safer, and lag-free communication only gets more aggressive by the day.

Keep in mind that RTP is not a one-size-fits-all solution to communication struggles. It works in tandem with other protocols to provide a customizable communication solution for businesses.

Thus, when evaluating vendors, ask how they handle security and make sure it’s compatible with what you want for your business. Also, ask what protocols they use and how—assuming you’ll know what they’re talking about. Maybe bookmark this page, just in case.


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