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Things to Look for In Class 4 Softswitch for Wholesale Service Providers

There are good times ahead for wholesale telecom carriers with the market expected to exceed $ 332 billion by 2025. It is also a challenging time with the rise of OTT services and 4G/5G in addition to increased media traffic that places a load on networks. Legacy class 4 softswitch proves inadequate and it is time to move to better softswitches that fit into next-generation networks.

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The enhanced class 4 softswitch

The wholesale VoIP traffic is expected to exceed over 550 billion minutes with growth pegged at 8% each year. Last year’s lockdown led to a growth of 70% in the duration of voice call sessions. Along with increased traffic comes the issue of security and a greater need for carriers to have exceptionally intelligent least-cost routing. Managing wholesale calls and billing is a monumental task for which you certainly need billing and payment gateway integration into the class 4 softswitch software. If your current softswitch is capacity or capability limited, it is time to move up to a better class 4 softswitch.

Protocol support and conversion, transcoding

VoIP traffic is more democratic these days with video and data sharing space with audio but this melange of protocols in use brings along compatibility issues. Your class 4 softswitch may be capable of handling a huge amount of traffic and offer the best security but if you come up against protocol conversions then it definitely affects the quality of service. You need softswitches that can easily handle older and newer audio and video protocols right up to the emerging H.265, and be capable of transcoding on the fly. It does not end there. Bitrate assumes the importance of high-quality audio and video but a compromise is needed keeping in mind bandwidth. You would want a solution that can take in 4K video at 13Mbps and transcode and transrate it to full HD or HD at 6Mbps or even down to 600 kbps. Likewise, particularly in audio, resizing video from 3840x2160 to 1280x720p should be accomplished on the fly with no discernible delay. Going a step further it may be necessary to transcode and use protocol conversion followed by repackaging into an adaptive streaming format such as HLS if required.

Redundancy and quality of service

If there is one thing wholesale carriers cannot afford it is downtime or break in service. Customers will leave in droves if this is a frequent occurrence. On-premise class 4 softswitch is good if it is advanced enough to handle NGN platform but a better option would be hosted class 4 softswitch software deployed in a multi-site geo-redundant system with call continuation consistency coupled with voice peering.

Routing

Older class 4 softswitches may employ a basic set of Least Cost Routing algorithms but today’s environment is more complex with an increase in the number of exchanges, the necessity to maintain older PSTN links and also take care of 4G/5G mobility and media. You need a softswitch that is smarter and factors in all these permutations. Features to consider would be:

  • LNP lookup with blacklist and whitelist

  • A/B number modification before and after lookup

  • Routing based on an audio codec

  • Selection based on number prefix

  • The Peer group was chosen on basis of originating SIP domain

  • Load sharing and balancing

  • Routing based on priority, preset proportion, QoS, caller ID, and so on

  • Custom processing of SIP headers

A filtered third-party routing engine does look good in today’s class 4 softswitch, especially when you have it aligned with built-in call detail records and billing engine.

Billing, CDR

It is simple and even legacy class 4 softswitch software includes it but at a rudimentary level. For tomorrow and current needs you need to enhance CDRs that are not just voice-based but also include video and media so that you can price each one differently if so desired. You need postpaid and prepaid models based on call detail records along with automatic reminders and notifications, currency flexibility, and the facility to set rates for each user. Integrating payment gateway is another indispensable feature. You will find it useful if the softswitch has tax options, financial analysis, price management, price list import/export, and configurable billing patterns.

Backward compatibility

PSTN is on its way out is what we have been hearing for so many years but, for the foreseeable near future at least, you need to be able to handle PSTN/TDM and your latest version of class 4 softswitch must have full backward compatibility features with support for protocols such as ISDN PRI, ISDN Net 5, ISDN/SS7 UUI mapping to SIPSS7/C7ISUP and others. Your class 4 softswitch must include A and F links supported E1 to DS3 mapping, delayed ANM for ISUP and ISDNISUP multilevel precedence, and preemption. Businesses still rely on standard phone lines even though the number and use are reducing. Better backward compatibility means retention of older customers, continuity, and more revenues.

Security, monitoring

Higher traffic means more vulnerability, especially since VoIP use is growing, making it attractive for hackers to launch attacks such as ransomware or DoS. You could consider vanilla class 4 softswitch but the smarter option is to pick softswitches that incorporate features of intelligent session border control. Security certainly improves and is doubled when you have an additional SBC in your network. Likewise, monitoring is desirable but may not be practical to get a smarter softswitch with artificial intelligence that will monitor and raise a flag should it detect anything unusual. Real-time monitoring covers active calls, user activity, CPU/RAM/Hard Disk utilization, and deviation. These are necessary, whether automated or manual.

In the current era where margins are wafer-thin and competition is cutthroat, quality of service assumes greater importance and one way to achieve this is to have in place the finest infrastructure and software that is current for today and tomorrow. Choosing a smart, intelligent class 4 softswitch does make a vast difference to your wholesale carrier operation.

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