Telos Zephyr iPort - Manual (Page 18)

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selected on the Diagnostics page. These are mostly intended for our engineers. Should you
have a problem that might be diagnosable via these logs, our support people will ask you to
download and email us the files.
FAQs
Do all the channels need to go to a single unit at the other end?
No. Each of the iPort’s channels are independent and may be used individually. Simply
enter the IP numbers/ports for the unit you want to use at the other end.
Can I use the iPort with Telos Z/IP or ZXS codecs at the other end?
Yes, with proper configuration.
Can I use the iPort with codecs from other manufacturers?
The iPort creates and consumes standard MPEG streams with standard RTP/UDP/IP
packet formatting - nothing proprietary or special. If another vendor’s codec conforms to
the standards, it should work with the iPort.
Does the iPort conform to the ITU N/ACIP specification?
No, it does not. The iPort is intended for a different class of applications. The N/ACIP
standard envisions VoIP call-like operation with SIP control, whereas the the iPort is
generally used in a ‘nailed-up’ way.
Our Z/IP codec family does conform to N/ACIP.
What about firewalls?
You will need to open the appropriate ports in your firewall. The IP and port numbers are
easily set/determined from the iPort’s Web pages, so you know which have to be opened.
This follows from the usual nailed-up applications for which iPort is intended.
Our Z/IP codec family has sophisticated technology for automatically punching through
many kinds of firewalls. To do so, it uses a special server that resides outside the firewall.
(This can be the one we operate as a service to Z/IP users, or one you operate yourself.) The
iPort has no way to use such a server because it does not use SIP for call set-up.
Which codec type should I use?
There are tradeoffs among those available in the iPort, with each having advantages and
disadvantages. That’s why we give you the choice. Here are some guidelines:
AAC is the best all-round codec for bitrates of 96kbps and above (stereo). It has
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excellent packet-loss concealment.
AAC-HE (AAC+) should be used at rates under 96kbps. It has good audio quality
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at 64kbps, and is pretty good even down to 48kbps. It also has good packet-loss
resilience, but not as good as AAC.
AAC-HEv2 is the most efficient codec for stereo. It has a new “parametric stereo”
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function that kicks-in at low bitrates. Rather than sending the left/right channels
discretely, it sends a core mono signal together with steering control. This makes
reasonable quality stereo possible down to 32kbps, and useful stereo even to 24kbps.