I tried VoIP a few years ago. The quality was okay for talking, but not good enough for broadcast transmission.

To overcome any complications with using public IP for broadcast transmissions, Telos Systems engineered Agile Connection Technology™, or ACT. This exclusive technology from Telos Systems is designed to optimize public-IP broadcasting. Utilizing ACT, the Zephyr/IP dynamically overcomes packet loss, jitter, limited bandwidth, Firewalls, NATs, as well as dynamic IP address changes. With overcoming these factors, delay is minimized and the Z/IP intelligently adjusts to available bandwidth to provide excellent audio quality. This is done automatically without you constantly adjusting settings. The Zephyr/IP also uses MPEG AAC-ELD, a new codec designed specifically to address these issues.

This sounds great, but complicated.

Configuration is simple and allows you to assign the unit a unique name and group membership for easy identification. The unit’s name and group allow it to be identified regardless of IP addresses and you control the units visibility to other Z/IPs on the network. You can configure the Z/IP through the full color VGA display or through a web interface. Wireless connections are configured in a simple four step process.

Why use a VGA display? A web interface is good enough.

There are situations where a web-interface is not convenient and can actually be limiting. In addition to a built-in web server, accessible by any web browser (even remotely), we give you a full-color VGA screen on the unit itself. This allows you to focus more on the important aspects of a broadcast.

What makes this device unique?

This is the only device on the market that continuously adapts itself to network conditions. During a five hour remote, you won’t have to worry about constantly having to adjust your settings to accommodate network changes or make short calls.
Beyond basic stability, the Z/IP is extremely user friendly to you and other VoIP devices. We use open standards for signaling (SIP), transport (RTP) and codecs (G.711, G.722, MPEG codecs, linear PCM). This allows the Z/IP unsurpassed compatibility with other devices. The Z/IP can register and accept calls from your VoIP PBX as long as it supports SIP 2.0 and the G.711 and G.722 codecs.

Digital is great, but I still have some analog gear. Will the Z/IP work with it?

The Z/IP accepts both digital and analog inputs. Analog is input using standard XLR connectors and accepts both pro and consumer input levels with a peak of +22dba.

I hear a lot of talk about compatibility and open standards.

Compatibility and the use of open standards is an important factor to consider when investing in your broadcast technology. The longevity of true compatibility can only be achieved by using a set of mutually agreed upon open standards that participants implement. The Zephyr/IP is fully compliant with the N/ACIP International Standard. The Z/IP is compatible with any device that uses these standards. By using Session Initial Protocol (SIP) the Z/IP works with TCP, UDP, DNS and other protocols. The Zephyr/IP also uses the Real-time Transport Protocol (RTP) to transmit audio data. RTP is used by VoIP telephony and is becoming standard for broadcast codecs. In addition to standard signaling and transport protocols, the Zephyr/IP contains a suite of codecs that adhere to the N/ACIP standard. The Zephyr/IP may even be able to talk to your existing VoIP PBX.

What is the Telos Z/IP Server? Do I need one of my own?

The Telos Z/IP Server is a free service, provided and maintained by Telos Systems. It provides enhanced features for the Z/IP. It allows name or phonetic (soundex) and wild card searches, directory services, be visible and reachable behind NATs and firewalls, exchange status notifications and determine location of other end points. We provide this service, including full service redundancy, so you don’t have to worry about it yourself.
If you don't want to use the Z/IP Server, the Z/IP will still work on any network including closed intranets, satellite links or other networks that are not connected to the Internet. When you are able to connect to the internet, the Z/IP Server will give you an enhanced experience.

What about software updates?

The Z/IP is fully updateable, for free, through the unit’s web interface. They’re downloadable at our website, and all of your settings are retained.

What is error concealment?

Error concealment is an inaudible technique of replacing lost audio packets without requiring retransmission and thus minimizes delay. The Codec keeps track of the audio frequencies used around the lost packet and creates a similar replacement. This is the best technique for handling packet loss in an interactive, two-way application. The algorithms employed on the Z/IP yield usable results with up to 20 percent random packet loss.

Why don't you use Forward Error Correction (FEC) instead of concealment?

Forward error correction works by sending the original audio packet along with some form of copy of this packet at a later time. If a packet gets lost it is replaced by the copy. This has two downsides: it increases the bandwidth usage (with lack of bandwidth being the likely reason why the packet was lost) and it increases delay. Using error concealment avoids both of these issues.

Why don't you use TCP to send the audio streams?

While TCP ensures that all of the data will get to the other side, it does this by using very large buffers and potentially very large delays. In most cases the delay is at an unacceptable level for two-way connections. We use RTP (transported over UDP) to get the minimum delay possible, suitable for two-way conversations.

Can I send a stream to multiple locations?

While the Z/IP generally supports one-to-one connections it is also capable of sending streams to multiple locations. We call this "push" mode in the manual.

How can I tell what the network conditions are during a call?

The Z/IP displays the approximate path taken by the audio on a world map along with the average delay introduced by each node. The path and node delay may change, but this information gives valuable clues about the network congestion. Additional screens display real-time statistics such as the number of packets lost, buffered, and concealed in both numeric and graphical formats.

How do I configure the Z/IP to use a wireless device?

1. Power up the Zephyr/IP without the device plugged in.

2. Once fully booted up, and the Main Menu is displayed, plug in the approved wireless device into either of the USB ports on the back.

3. Navigate to the main Network Menu and select Wi-Fi / WLAN. Enter the hostname for the wireless network (ESSID Network Name and Encryption Key as well for Wi-Fi). Press “Activate Settings” to commit your changes.

4. ESC back to the main Network Menu and choose “Wi-Fi / WLAN” for a Wi-Fi device, or choose “UMTS” for a cellular device.

You will now be using the mobile device to make a call.

What wireless devices does the Z/IP support?

The Zephyr/IP uses common (non-proprietary) wireless devices. The Z/IP currently supports the following devices. Check back regularly since the list will be expanding:

Wi-Fi
• Linksys Compact Wireless – G USB Adapter, 24Ghz

EVDO / Mobile Broadband
• Sierra Wireless USB device AC595U for Sprint or Verizon
• Novatel Ovation U727

How does the Zephyr/IP perform in real-time?

A real-time, delay-free transmission requires a high-quality, stable, and dedicated connection such as a closed Intranet, satellite link or other (non-public) connection. The Zephyr/IP excels in performance over both controlled and non-controlled connections, such as public-IP. Using advanced codecs and Agile Connection Technology, the Zephyr/IP produces high-quality transmissions, with very little delay, without needing you to constantly ‘tweak’ the settings.

Why audio over IP? Why not stick with ISDN or GSM?

With the growth of the Internet, service providers are slowly discontinuing ISDN. This is also the case with GSM. In addition to IP’s widespread availability, IP connections do not have multi-week lead times, costly set-up and per-minute charges. The Zephyr/IP uses exclusive technology to overcome the complications with public-IP audio transmission and is optimized for real-world conditions.

I thought that your products only used Ethernet for transmission within a facility.

The Zephyr/IP has been designed for exceptional transmission within a facility as well as over public IP and wireless mobile connections, such as at remotes. Not only does the unit provide superior functionality over public IP, the free Z/IP Server further enhances IP audio transmission by removing the complications. In addition to Ethernet connections, we include parallel, AES/EBU, USB, RS-232, analog, and even an extra PCI card slot.

What about remotes?

Among other features, the Z/IP Server provides dial-by-name functionality and traverses tough firewalls and NATs. If you have a long broadcast planned, you won’t need to make multiple short calls. The Z/IP Server works hard to keep you connected and handles dynamic IP address changes. Dial-by-name functionality eliminates the need for reprogramming your unit if your area code is changed. The Z/IP Server can act as a media relay if both Z/IP units are behind especially troublesome firewalls or NATs. The new Z/IP Mixer combines the versatility of the Zephyr/IP with the utility of a digital four-channel stereo mixer, all in a rugged, road-ready portable chassis.

Do I need to buy an upgrade for these codecs or functionality?

The Zephyr/IP has the complete suite of codecs and dynamic functions without needing any upgrades or options purchased.

I thought that quality over a mobile connection isn’t that good.

The Zephyr/IP uses Agile Connection Technology (ACT) to provide you with excellent quality audio over mobile connections. The Zephyr/IP is designed to work with standard existing mobile phone connections and optimize available bandwidth to provide excellent quality audio with very little delay.

What about international connections?

Since the Z/IP uses internationally adopted open standards, there is no need to worry about international connections or buying a special international model. Dial-by-name, directory look-up, and “group speed-dial” features make international calls as easy as calling a unit in the same room.

Can the Z/IP place regular phone calls?

The Zephyr/IP can place regular voice calls with very little configuration needed. If they Zephyr/IP has already been configured to use a wireless connection, all you need to do is change the streaming device in the main Network Menu. The Z/IP uses an intuitive display that presents context-sensitive help.

I thought that packet based audio transmission through the Internet was bad.

Agile Connection Technology solves the problems with packet based transmission to where it is the favorable protocol to use. ACT uses dynamic monitoring to adjust itself for optimum performance given the current network conditions. This includes dynamic buffering, jitter correction, and packet-loss concealment, just to name a few.

What will happen if one of the public-IP transmission relay points, or hops, goes down?

Every packet of your audio transmission can take completely unique routes. If a relay point goes down, the other packets will simply not take that route. The Zephyr/IP handles the unpredictable arrival of packets (jitter) by dynamically adjusting itself dynamically while optimizing quality and minimizing delay.