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Sunday, December 31, 2006

Saturday, December 30, 2006

XSAN vs Fibrejet

Digistor: "Xsan vs Fibrejet

Commandsoft have released a quite detailed pdf showing the differences, as they see them, between XSAN and Fibrejet. It's worth a read as it goes into reasonable detail about SAN's in general.

It's a rather large file (4MB) and can be downloaded
here

Creative Cow - View Posts - Apple Xsan

Creative Cow - View Posts - Apple Xsan

Xsanity - Sanity for Apple's Xsan.

Xsanity - Sanity for Apple's Xsan.

Xsan: Information from Answers.com

Xsan: Information from Answers.com

ADIC StorNext File System: Information from Answers.com

ADIC StorNext File System: Information from Answers.com

Apple XSAN is licensed from ADIC StorNext.
Carrier Grade Linux - Wikipedia, the free encyclopedia

Monday, December 25, 2006

ECI Telecom

Carrier-grade optical (C/DWDM) and broadband access platforms.

Sunday, December 24, 2006

Outlook, Appointments and Time Zones
LinuxElectrons - linux with a hardware slant
SQL Server Reference Guide > SQL Server 2005 - Service Broker: "If you think about how you go through your day, you'll find that you don't always stand in a line (or a queue, for my non-American readers) for everything you do. You get into your car; stop at a gas (petrol) station, which has been open all morning. That station has serviced many cars, without knowing who would come in first or last. You then drive to a coffee shop to buy a latte, again open since morning and again servicing many customers in multiple orders. You may decide not to stop at the coffee shop, or choose another. You choose one road over another to get to work, park in different parking spaces each day, and so on. Each of the 'objects' you're interacting with in your world on a day-to-day basis provides you a service, and you often have multiple choices of providers of those services.

You can set up your infrastructure to work the same way. Rather than having a single server process a purchase order for your company, you could break up the 'services' in that process and have multiple servers process the request. Your client application can ask the system which server provides a needed service and route the request to a server based on location, load, speed or security. This arrangement is called a 'Service-Oriented Architecture' or SOA, and while it takes a lot of planning and forethought to set up, it's very powerful."

Saturday, December 23, 2006

Friday, December 15, 2006

Monday, December 11, 2006

Network Performance Daily: Vista's "Next Generation" TCP/IP Stack and the Enterprise

Network Performance Daily: Vista's "Next Generation" TCP/IP Stack and the Enterprise
Fundamentals of DS3
Scott Weeks Re: M23 vs M13 DS3 Muxing Thu 12/7


-----------------------------------------------------------------------
> M23 is definitely different than M13. The 1 and 3 refer to T1 and T3.
> In M23, it refers to T2 and T3! I don't know if anyone ever deployed
> T2 in North America but it still exists in some places.

"M13 multiplexing is done in two steps. First, four T1 lines are bit multiplexed together to form a DS2 line using M12 multiplexing. These seven DS2 lines are then bit multiplexed together to form the DS3/T3 using M23 multiplexing."
------------------------------------------------------------------------


A great resource for DS-3 info is what used to be TTL's "Fundamentals of DS3". You can find it here:

http://mauigateway.com/~surfer/library/fundamentals-of-DS3.pdf


I also have others. Some are TTC's and some are Acterna's:

http://mauigateway.com/~surfer/library/fundamentals-of-SONET.pdf
http://mauigateway.com/~surfer/library/fundamentals-of-T1.pdf
http://mauigateway.com/~surfer/library/fundamentals-of-ADSL.pdf
http://mauigateway.com/~surfer/library/fundamentals-of-ethernet.pdf

_______________________________________________
"Eat sushi frequently". - Avi
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Eric J Merkel Re: M23 vs M13 DS3 Muxing Thu 12/7

Actually, the M23 framing works just fine. We found the problem to be in the channel mappings on our switch. Apparently, our switch programmer started at interface 1 when he should have started at 0. The Cisco T1 controller interface starts at 1 and the switch at 0 so the SS7 signaling was mapping channels to the wrong interface. Basically interface 1 went to 2, and 2 to 3 and so on and there the COT tests would not pass. DOH!!!

After talking to several telco people, apparently even though their framing says M13 it is actually converting four DS1's into a DS2, then mapping the 7 DS2's up to the DS3 level. I guess both ADTRAN and Alcatel group them this way with the M13 option so it isn't truly doing a straight DS1 to DS3 conversion. So the M23 & M13 framing are somewhat synonymous on this equipment though that is technically they should call it M23 not M13.

FWIW, we also tried C-bit and had the same problems which took us down the path of trying to figure out why the channels weren't syncing. Just the lovely part of SS7 where signalling takes place out of band.

Thanks for everyone's suggestions.

-Eric

----- Original Message -----
From: "Adam Rothschild"
To:
Sent: Thursday, December 07, 2006 2:34 PM
Subject: Re: M23 vs M13 DS3 Muxing


> On 2006-12-07-12:32:03, Jawaid Bazyar
> wrote:
>> M23 is definitely different than M13. The 1 and 3 refer to T1 and
>> T3. In M23, it refers to T2 and T3! I don't know if anyone ever
>> deployed T2 in North America but it still exists in some places.
> [...]
>
> M23 (as opposed to c-bit parity) is most definitely a valid means of
> delivering T1 tails off a carrier's CT3 facilities. Whether or not
> you want it depends on your particular carrier's configuration.
>
> For example, on a Level(3) (formerly LGN) circuit 'round here:
>
> [email protected]> show interfaces t1-5/3/0:0
> Physical interface: t1-5/3/0:0, Enabled, Physical link is Up
> [...]
> Link-level type: Cisco-HDLC, MTU: 1504, Clocking: Internal, Speed: T1,
> Loopback: None, FCS: 16, Mode: M23,
> Framing: ESF ^^^^^^^^^
>
> Definitely worth a try if c-bit isn't working.
>
> HTH,
> -a
> _______________________________________________
> "Eat sushi frequently". - Avi
> [email protected] is the human contact address.
> [email protected] is the list posting address.
> See below URL for subscribe/unsubscribe and list options:
> http://inet-access.net/mailman/listinfo/list
>

_______________________________________________
"Eat sushi frequently". - Avi
[email protected] is the human contact address.
[email protected] is the list posting address.
See below URL for subscribe/unsubscribe and list options:
http://inet-access.net/mailman/listinfo/list

Friday, December 01, 2006