Remote PBX Extension

Hello,

I've a customer who has two premises close to one another.

On each building is a Motorola "Square-ial" supplying a microwave link
for the two sites' single LAN.

Q1. Is this likely to be a duplex link?

Q2. If Q1 is yes, anyone got any suggestions for getting a phone
connected in site 2 to site 1's analogue PBX?

for Q2, I was thinking of an SPA3102 at the PBX end and an SPA2102 at
the remote end; I've never been overly impressed with the SPA3102's
voice quality WRT PSTN.

Can Grandstreams be connected back-to-back like the SPAs? (see
<http://www.provu.co.uk/pdf/sipura/spa_backtoback_1x_spa3000_and_1x_spa1001.pdf>
for what I mean)

If Grandstreams can, which models should I use?

Thanks.

In article <mn.44df7d87aa3b5b37.88534@blueyonder.invalid>,
Jono <nothanks@blueyonder.invalid> wrote:
>Hello,
>
>I've a customer who has two premises close to one another.
>
>On each building is a Motorola "Square-ial" supplying a microwave link
>for the two sites' single LAN.
>
>Q1. Is this likely to be a duplex link?

If it's a Canopy system, then yes, it's full duplex as far as it allows.
(I used to work for them) There are 2 basic models though - a fast one
and a slow one. They have E1 adapters for them, (E1 to Ethernet) so if
they can do that sort of stuff, then pure VoIP ought to be a doddle.

>Q2. If Q1 is yes, anyone got any suggestions for getting a phone
>connected in site 2 to site 1's analogue PBX?

Throw away the Analogue PBX in site 1 and install a new hybrid PBX :)

>for Q2, I was thinking of an SPA3102 at the PBX end and an SPA2102 at
>the remote end; I've never been overly impressed with the SPA3102's
>voice quality WRT PSTN.
>
>Can Grandstreams be connected back-to-back like the SPAs? (see
><http://www.provu.co.uk/pdf/sipura/spa_backtoback_1x_spa3000_and_1x_spa1001.pdf>
>for what I mean)

You can do direct IP dialling on Grandstreams.

>If Grandstreams can, which models should I use?

How much money? They're all about the same in the BT200, through the
GXP2000s .. For a simple phone the BT200 is adequate, but it's display
is digits only. I think it has a "bat phone" mode too, so just lift the
handset and the other one will ring...

Gordon

On Tue, 08 Jul 2008 20:47:24 +0100, Jono wrote:

> On each building is a Motorola "Square-ial" supplying a microwave link
> for the two sites' single LAN.
>
> Q1. Is this likely to be a duplex link?

'iperf' will tell you. Run a duplex test [-d] then a tradeoff test [-r]
and if there's a massive difference between the two, then it's probably
not full duplex.

Also, running it in UDP mode will tell you the jitter and loss for the
bandwidth and packet size you give it. For example on my switched fast
ethernet LAN, I started iperf in UDP server mode with a packet length of
160 bytes, roughly what you'd see with SIP in G.711:

hostA# iperf -s -u -l 160

Then on another machine, UDP mode, 100kbps, 160 byte packets, for 60
seconds:

hostB# iperf -u -c hostA -b 100k -d -l 160 -t 60

Client connecting to 192.168.1.28, UDP port 5001
Sending 160 byte datagrams
UDP buffer size: 120 KByte (default)
------------------------------------------------------------
[ 3] local 192.168.1.3 port 51712 connected with 192.168.1.28 port 5001
[ 4] local 192.168.1.3 port 5001 connected with 192.168.1.28 port 34038
[ 3] 0.0-60.0 sec 733 KBytes 100 Kbits/sec
[ 3] Sent 4689 datagrams
[ 4] 0.0-60.0 sec 733 KBytes 100 Kbits/sec 0.003 ms 0/ 4689 (0%)
[ 3] Server Report:
[ 3] 0.0-60.0 sec 733 KBytes 100 Kbits/sec 0.002 ms 0/ 4689 (0%)


So jitter and packet loss are almost non-existent, and as a result VoIP
is excellent. Wirelessly:

Client connecting to 192.168.1.33, UDP port 5001
Sending 160 byte datagrams
UDP buffer size: 120 KByte (default)
------------------------------------------------------------
[ 3] local 192.168.1.3 port 50076 connected with 192.168.1.33 port 5001
[ 4] local 192.168.1.3 port 5001 connected with 192.168.1.33 port 54587
[ 3] 0.0-60.0 sec 733 KBytes 100 Kbits/sec
[ 3] Sent 4689 datagrams
[ 4] 0.0-60.0 sec 733 KBytes 100 Kbits/sec 1.573 ms 0/ 4689 (0%)
[ 3] Server Report:
[ 3] 0.0-60.0 sec 732 KBytes 99.9 Kbits/sec 1.406 ms 4/ 4689
(0.085%)

A bit of packet loss and much more jitter, but VoIP is still spotless.
Finally, over a DSL-DSL VPN:

------------------------------------------------------------
Client connecting to 192.168.253.9, UDP port 5001
Sending 160 byte datagrams
UDP buffer size: 120 KByte (default)
------------------------------------------------------------
[ 4] local 172.29.25.1 port 58212 connected with 192.168.253.9 port 5001
[ 3] local 172.29.25.1 port 5001 connected with 192.168.253.9 port 59885
[ 4] 0.0-60.0 sec 733 KBytes 100 Kbits/sec
[ 4] Sent 4689 datagrams
[ 3] 0.0-60.0 sec 733 KBytes 100 Kbits/sec 0.950 ms 0/ 4689 (0%)
[ 4] Server Report:
[ 4] 0.0-60.0 sec 733 KBytes 100 Kbits/sec 0.847 ms 0/ 4689 (0%)


So over the WAN looks better than wirelessly.

> Q2. If Q1 is yes, anyone got any suggestions for getting a phone
> connected in site 2 to site 1's analogue PBX?

Even if it's not full duplex, then for light use it should be OK.

> Can Grandstreams be connected back-to-back like the SPAs?

Anything that will let you dial by IP [and let you put that number on a
speed dial or sofkey] without registration will do.

--
<http://ale.cx/> (AIM:troffasky) (UnSoEsNpEaTm@ale.cx)
23:01:02 up 7 days, 9:28, 3 users, load average: 0.25, 0.12, 0.10
Convergence, n: The act of using separate DSL circuits for voice and data

alexd explained on 09/07/2008 :
> On Tue, 08 Jul 2008 20:47:24 +0100, Jono wrote:


Snipped bits that went Whoosh...will study them later, thanks.
>
> So over the WAN looks better than wirelessly.
>
>> Q2. If Q1 is yes, anyone got any suggestions for getting a phone
>> connected in site 2 to site 1's analogue PBX?
>
> Even if it's not full duplex, then for light use it should be OK.

Ah, OK.

>
>> Can Grandstreams be connected back-to-back like the SPAs?
>
> Anything that will let you dial by IP [and let you put that number on a
> speed dial or sofkey] without registration will do.

Yeah, I know, however, what else, other than an SPA3102 would let me
connect to an analogue extension port?

Gordon Henderson used his keyboard to write :
> In article <mn.44df7d87aa3b5b37.88534@blueyonder.invalid>,
> Jono <nothanks@blueyonder.invalid> wrote:
>> Hello,
>>
>> I've a customer who has two premises close to one another.
>>
>> On each building is a Motorola "Square-ial" supplying a microwave link
>> for the two sites' single LAN.
>>
>> Q1. Is this likely to be a duplex link?
>
> If it's a Canopy system, then yes, it's full duplex as far as it allows.
> (I used to work for them) There are 2 basic models though - a fast one
> and a slow one. They have E1 adapters for them, (E1 to Ethernet) so if
> they can do that sort of stuff, then pure VoIP ought to be a doddle.

That could be useful....do you have any pictures of any that I can look
at to decide what it is I'm working with?

I'm probably going to stick Asterisk on a laptop and take a couple of
snoms to site to see if it works.

>> Q2. If Q1 is yes, anyone got any suggestions for getting a phone
>> connected in site 2 to site 1's analogue PBX?
>
> Throw away the Analogue PBX in site 1 and install a new hybrid PBX :)

I was a little less than full with my description; it is a Panasonic
Hybrid, with VoIP etc. Unfortunately, this 2nd site needs a cordless
phone. I was hoping to use something like the Siemens, purely as an IP
extension off the panasonic. Unfortunately, Panasonic's implimentation
of VoIP means that transferring calls from the cordless doesn't work.

As I've got spare SLT ports, if I can get a regular DECT connected but
linked over the microwave, then all the system functions will be
available that are currently enjoyed on all the analogue extensions.

>
>> for Q2, I was thinking of an SPA3102 at the PBX end and an SPA2102 at
>> the remote end; I've never been overly impressed with the SPA3102's
>> voice quality WRT PSTN.
>>
>> Can Grandstreams be connected back-to-back like the SPAs? (see
>> <http://www.provu.co.uk/pdf/sipura/spa_backtoback_1x_spa3000_and_1x_spa1001.pdf>
>> for what I mean)
>
> You can do direct IP dialling on Grandstreams.
>
>> If Grandstreams can, which models should I use?
>
> How much money? They're all about the same in the BT200, through the
> GXP2000s .. For a simple phone the BT200 is adequate, but it's display
> is digits only. I think it has a "bat phone" mode too, so just lift the
> handset and the other one will ring...

As little as possible! I need something that plugs in to a regular
analogue extension port on the PBX at one end and at the other, gives
me an analogue port to plug a dect base in.

In article <mn.4d737d87af103e2a.88534@blueyonder.invalid>,
Jono <nothanks@blueyonder.invalid> wrote:
>alexd explained on 09/07/2008 :
>> On Tue, 08 Jul 2008 20:47:24 +0100, Jono wrote:
>
>
>Snipped bits that went Whoosh...will study them later, thanks.
>>
>> So over the WAN looks better than wirelessly.
>>
>>> Q2. If Q1 is yes, anyone got any suggestions for getting a phone
>>> connected in site 2 to site 1's analogue PBX?
>>
>> Even if it's not full duplex, then for light use it should be OK.
>
>Ah, OK.

Wi-Fi is not full duplex, but VoIP works OK over it, if there's nothing
else - it can suffer from ethernet capture effect though.

>
>>
>>> Can Grandstreams be connected back-to-back like the SPAs?
>>
>> Anything that will let you dial by IP [and let you put that number on a
>> speed dial or sofkey] without registration will do.
>
>Yeah, I know, however, what else, other than an SPA3102 would let me
>connect to an analogue extension port?

I've used a Grandstream HT488 in the past, but I'm not 100% happy with
them.

Gordon

Jono wrote:
> As I've got spare SLT ports, if I can get a regular DECT connected but
> linked over the microwave, then all the system functions will be
> available that are currently enjoyed on all the analogue extensions.

Why not use the analogue port of a Siemens phone, and also stick in a
DECT repeater?



Tim

Tim submitted this idea :
> Jono wrote:
>> As I've got spare SLT ports, if I can get a regular DECT connected but
>> linked over the microwave, then all the system functions will be available
>> that are currently enjoyed on all the analogue extensions.
>
> Why not use the analogue port of a Siemens phone, and also stick in a DECT
> repeater?
>
>
>
> Tim

The distance may be a bit too great; it wouldnt have to be a Siemens as
any DECT would do if I could use repeaters.

Jono wrote:
> The distance may be a bit too great; it wouldnt have to be a Siemens as
> any DECT would do if I could use repeaters.

Siemens phones seem to go further than any other DECT phone I've played
with.

Tim

Tim wrote on 10/07/2008 :
> Jono wrote:
>> The distance may be a bit too great; it wouldnt have to be a Siemens as any
>> DECT would do if I could use repeaters.
>
> Siemens phones seem to go further than any other DECT phone I've played with.
>
> Tim

ah, right. I see the logic in the suggestion.

I've not studied repeater deployment at all - is there a Siemens
repeater or would you suggest a generic one?

Jono wrote:
> I've not studied repeater deployment at all - is there a Siemens
> repeater or would you suggest a generic one?

There is a Siemens repeater and a Snom repeater (which we have in
stock). Both work with Siemens phones.

I'll dig out the prices and stuff.

Tim