Ericsson is this week re-entering the market for DSLAMs with an innovative Ethernet access card that it says will unlock the mass market for DSL services by . DSLAM units are typically located in telephone exchanges or distribution points. They allow for the high-speed transmission of DSL technology. Ericsson’s EDA solution is the most widely deployed IP/Ethernet DSLAM with over 60 contracts globally, utilizing the latest ADSL2+ technology.

Author: Malazahn Brabar
Country: Comoros
Language: English (Spanish)
Genre: Technology
Published (Last): 21 January 2018
Pages: 18
PDF File Size: 15.91 Mb
ePub File Size: 3.25 Mb
ISBN: 601-5-31597-258-1
Downloads: 66485
Price: Free* [*Free Regsitration Required]
Uploader: Daijinn

There was zero indication of the potential for this to happen, until it started happening this week. This sort of resiliency is at the heart of why these systems are generally just rock solid in practice.

The intention of writing this down is transparency — something we love. Multiplexing Digital subscriber line. Like traditional voice-band modems, a DSLAM’s integrated DSL modems are usually able to probe the line and to adjust themselves to electronically or digitally compensate for forward echoes and other bandwidth-limiting factors in order ericzson move data at the maximum possible connection rate.

Internode The Web Search Search. What is left, therefore just like the airline situationare the truly unusual failure modes. User traffic is mostly IP based.

Ericsson EDNX IP DSLAM Module | eBay

Archived from the original on It also uses the best equipment and services it can obtain — because this erricsson all a part of giving our customers the best possible service experience. But because it was a truly unusual failure mode, and also just because we care a hell of a lot about such things, we dropped everything to resolve it.

Each modem on the aggregation card communicates with a single subscriber’s DSL modem. The only thing that has been demonstrated to stop the fault is to upgrade the ECN software to a newer release.

Once they caught a cold, they kept it. This is due dspam the nominal line impedance measured in Ohms but comprising both resistance and inductance of balanced lines being somewhat lower than that of UTP, thus supporting ‘weaker’ signals however the solid-state electronics required to construct such digital interfaces are more costly.

Unsourced material may be challenged and removed. DSLAMs are also used by hotels, lodges, residential neighborhoods, and other businesses operating their own private telephone exchange.


Our vendor has eriscson identified a bug that is consistent with our observed outcome, and on their advice, we upgraded to the next revision of the code concerned in which that specific bug had been ericswon. The DSLAM equipment collects the data from its many modem ports and aggregates their voice and data traffic into one complex composite “signal” via multiplexing. Articles needing additional references from December All articles needing additional references All articles with unsourced statements Articles with unsourced statements from December Commons category link is on Wikidata.

Please help improve this article by adding citations to reliable sources. Views Read Edit View history.

InterComms – The International Communications Project

But it is much more than that. Customer-premises equipment that interfaces well with the DSLAM to which it is connected may take advantage of enhanced telephone voice and data line signaling features and the bandwidth monitoring and compensation capabilities it supports. Typically a single DSLAM aggregation card has 24 ports, but this number can vary with each manufacturer. Ericssson, so what happened? RSS feed for comments on this post.

An ECN looks like a 24 port ethernet network switch.

Ericsson EDN312X IP DSLAM Module

This article needs additional citations for verification. The following is a rough guide to the relation between wire distance based on 0. Retrieved from ” https: Internode engineers a lot of redundancy and resiliency into its network services. It has been, and it remains, a very unusual failure mode, starting with this interesting fact — when things went wrong, rebooting the applicable parts of our equipment did not fix those network elements.

Each DSLAM has multiple aggregation cards, and each such card can have multiple ports to which the customers’ lines are connected.

Ethernet DSL Access unlocks the broadband mass market

Therefore, it cannot re-route traffic between multiple IP networks, only between ISP devices and end-user connection points. This has been a complicated week!

The anatomy of a complex fault. We obviously had a fault. Like modern airlines, all the routine causes of breakdowns have largely been engineered away. December Learn how and when to remove this template message. This compensation capability also takes advantage of the better performance of ” balanced line ” DSL connections, providing capabilities for LAN segments longer than physically similar unshielded twisted pair UTP Ethernet connections, since the balanced line type is generally required for its hardware to function correctly.


By using this site, you agree to the Terms of Use and Privacy Policy. It is important to appreciate that the current software release the faulty one was rolled out very carefully as all upgrades normally areand it dslak been flawlessly for around five months until this fault developed. Last night we erocsson a few more switches not yet upgraded start to demonstrate the fault.

During reboot, the DSLAM modules maintain physical line fslam to the customer, but obviously data flow stops. Dlam digital subscriber line access multiplexer DSLAMoften pronounced DEE-slam is a network device, often located in telephone exchangesthat connects multiple customer digital subscriber line DSL interfaces to a high-speed digital communications channel using multiplexing techniques.

Accordingly, through this ring architecture, if there is a loss of any single: As I write this, the network is back to operating in a normal and stable manner. So far, updating an ECN to that newer software release erucsson resolved the issue on all customers attached to that affected ECN.

They are boot servers, control nodes, statistical aggregation points, and a number of other ericsdon including, also, being the ethernet switches that they appear, at face value, to be.

In response we proactively upgraded another significant proportion of the switches in the entire SA network. The current theory, based on vendor feedback, is that the software fault is a latent, load triggered, memory leak that makes the ECN lose the plot in a manner that corrupts some critical item inside ericsaon of the ECN systems — an item that remains corrupted after it is rebooted or power cycled. Based on vendor advice, we are now looking at how best to upgrade the rest of the network, to guard against a further recurrence elsewhere.

This modem functionality is integrated into the DSLAM itself instead of being done via an external device like a 20th-century voiceband modem.

Thursday, April 1st, by Simon Hackett. Posted in Broadband by Simon Hackett.