Valiant Products

The following is my understanding of the products of Valiant Communications. I was asked to do this by one of my relatives. Hope this helps him. BTW, my knowledge is not 100% correct and I expect the tech-masters like KG to correct the mistakes, if any.

E1 to T1 Converters:
Concept:
E1 and T1 correspond to two different data rates at which some communication takes place. As the name suggests, this product will be used in places where there is a need to inter-operate between E1 and T1 links.

E1 link is a group of 32 channels of 64 kbps each while T1 link is group of 24 channels of 64 kbps each. Therefore, for connecting 96 users of E1 system to another set of 96 users of a T1 system: there has to be 3 E1 links and 4 T1 links each connected to an E1/T1 converter.

Actual Usage example:
In Cellular networks, the link between Base Station Transceiver system (BTS) and the core network is based on E1 or T1 links. The BTS developed these days would be having the provision of E1 to T1 conversion and vice versa, so that they can be deployed independently of the type of core n/w in a particular locality.

Prospects:
The product of VCL in addition to E1/T1 also has a 10 BaseT rate conversion (or switching) facility. Conceptually, the rate conversion from E1 to T1 or in other words connecting an E1 system with a T1 system is not too complicated. The complexity might increase when the systems being cross-connected vary greatly in data rates.

Google Count: 10th. Also Valiant has a sponsored advertisement in Google search results.

STM-1/4 Multiplexers with E1, E3
Concept:
These are used to interconnect an optical fiber communication system with a low rate network like an Ethernet/E1/T1 system. As you would have noticed from the specification document from Valiant website, this product basically does rate adaptation from an STM (Synchronous Transfer Mode – a set of protocol for optical fiber communication) to a low data rate network.

Usage Example:
A BTS has to be connected to the core network of a GSM system (like BSC-MSC-HLR etc); the BTS has an E1/T1 facility. Instead of having a dedicated E1/T1 link between an individual BTS and a BSC (a BSC would be connected to a group of BTSs), a group of BSCs can access the BTS through the same optical fiber link. The STM-1/4 Multiplexers would be employed here.

Complexity:
A simple construction optical fiber is complex. If we do some additional operation on it (multiplexing), the complexity increases many times. To put it simply, any thing to do with optical fiber is complex, as both electromagnetic and physical factors affect the performance.
Drop-Insert Multiplexer:
Concept:
In a multichannel transmission system like E1/T1, ‘drop and insert’ refers to taking away (or diverting) the signal from one channel and using this channel to send some other information which in itself could have been taken (dropped) from another channel.

Usage Example:
Not clear. But my crude idea is as follows: There is a T1 link (24 channels), which are already occupied. If a high priority need arises for the usage of the resource, then one of the already occupied channels will be dropped (or diverted to a less efficient route or temporarily disconnected) and this high priority need will be given access to the network resource.


Complexity:
It depends on what we do with the dropped signal. Whether we simply release the ongoing channel or divert it to a less efficient channel. If it is the former, the complexity is not very high. For the latter, the complexity would be more. A caveat: this is the first time I am hearing about drop & insert principle (outside GSM). I would like to give a small example for the same. “Ronak and Rena are using the only two phone lines available at 20 Thambiareddy and Ramalingom has to talk to Rajan auditor regarding an accounting related issue. Ramalingom’s need has to be addressed immediately and one of the two (rena/ronak) must immediately release their connection so that Ramalingom can use the same. But who will release the connection (ronak or rena) is a complex issue. Another complex issue is how will that person (who has got disconnected) handle the situation. Will he/she sit quietly for Ramalingom or (ronak/rena) to finish or goes to Chemba demanding the cell phone”? [Characters: Ronak and Rena – Kids. Ramalingom – My dad. Rajan – My dad’s auditor. Chemba – Ronak’s mother]

GSM Gateways:
Concept:
A GSM network needs to be connected to a PSTN (Public Switched Telephone Network) so as to enable communication between the GSM n/w and the PSTN. Gateways are the interfaces between the GSM n/w and PSTN.

Usage Example:
A Hutch subscriber needs to be connected to a BSNL subscriber.

Complexity:
It would be equivalent to that of a usual switch. Since VCL also provides interface between GSM and VoIP, VoATM, VoFR, et al the complexity would be higher. The value added features offered by VCL are worth taking note. The interlinking of GSM and VoIP is extremely interesting. I am hearing about Voice over ATM networks (VoATM) and Voice over Frame Relay Network (VoFR) for the first time, so I reserve my comments. The dual band capability for GSM (900 MHz and 1800 MHz) and the auto-sense/auto switching capability mean the same product could be used for future 3G networks if the Gateway is coupled with VCL’s other product, STM-1 multiplexer. Very interesting.

Echo cancellers:
These will be used only in voice networks or in data networks offering voice capability. Echo cancellers in a normal E1/T1 link are not complex. Since I do not know about VoIP, VoFR, VoATM, I cannot comment on the complexity of echo cancellers in these networks. It also depends on how successful the concept of voice over FR, ATM networks be in the future. With the relatively less penetration of ATM/FR networks in a commercial scale, VoFR/VoATM will take time to come into full swing.

Voice compression:
Concept:
Reduce the rate at which voice (analog) is sampled and use some digital signal processing techniques so that the voice quality is good enough.

Complexity:
Medium. The key lies in not just decreasing the sampling rate but the use of certain ADSP algorithms that enhance the speech quality even at the low data rate.

Usage:
Almost in all voice communication system.

Thin route DCME:
Includes the features of Voice compression, echo cancellers.

The other products have the features described above in different combinations.