Wednesday, 9 October 2013

SIP Based Call Centres - 12 years on - Time for a light weight cloud approach to contact centre architectures

Back in 2001 - Wow that seems a long time ago now that I sit here in Oct 2013, I wrote a white paper which was published back then by the International Engineering Consortium in their Annual Review of Communications, called SIP Based Call Centres - A vendor independent architecture for multimedia contact centres and thanks to the Internet can still be found out there.

In the paper I sang the virtues of open standards and SIP for building contact centres capable of meeting the needs of a modern multimedia environment (voice, video and Instant messaging and presence). Since then (IMHO) SIP has become quite frankly bloated by extension after extension, and one SIP doesn't necessary work with another SIP, so SBC now have to mediate between different flavours.

I think its time to revisit signalling and communications in modern contact centre, after all the point is to let customers reach someone who can help them in whatever way best suites the customers need, in an efficient no frills way.

On reflecting on what I wrote 12 years ago and the current surge of interests in WebRTC and all things HTML and cloud, it struck me. Now is the time to rethink the way we build multimedia contact centres both for the customer and the business that uses them. Actually it wasn't too new a thought - I'd already put some top level architecture ideas together about a year ago when looking at a new approach to telecare with some colleagues over at Inmezzo. The approach for the next generation of contact centres means a much lighter footprint - no complex clients to use for the agents, no nasty plugins in the browser for customer, integration with the PSTN, voice, video and text chat from desktop or smart phone.

What doesn't change is the basic requirements for session queueing and routing, or the ability to present information about the contact.

So what does this new architecture look like.... Well I'll leave my thoughts on that for the next blog entry.

Monday, 7 October 2013

We are entering a new era of software defined communications

What now feels like a life time ago back in the dim and distant past ,OK - not so dim and distant 1980s, I was a young apprentice engineer with my training and interests firmly focused on Hardware (micro electronics more specifically). In 1987 I made the bold step towards software engineering as a choice, since it seemed, back then, that software was the way forwards to creativity and new solutions for communications. Having "converted" to software engineering by way of a degree in Computer Science at Aberystwyth University, I then continued in that vain becoming a professional software engineer. I still didn't forget the electronics that got me started, and this combined with software engineering put this to good use as a telecommunications engineer. Moving through the heady days of Nortel Passport Frame Relay Switches, Cisco AGS and MGS routers and Cabletron hubs.

Then the Internet happened.......

For the telecoms engineers out there (like me), in my humble opinion (IMHO) SDN is the networking equivalent of softswitches? The OpenFlow API is what MEGACO/SIGTRAN is to soft-switching and the so-called Orchestration layer the Stored Program Control Logic from the switch fabric and routing fabric. The media gateway is the Hardware forwarding platform (L2 switch fabric being physical of logical vSwitch, Microsoft Network Virtualisation and Virtual Subnet Identifiers), not to mention MPLS enabled VPLS and the rest of the MPLS "family".

And now in the telecoms field we're getting all excited about Network Function Virtualisation (NFV - . This is really about extending the Virtualisation platforms/techniques like those provided by VMWare ESX and Microsoft HyperV into the telecoms space and placing the Functional elements of the NGN network on these virtualisation platforms. As the ETSI White paper states:

"leveraging standard IT virtualization technology to consolidate many network equipment types onto industry standard, high-volume servers, switches and storage."

This allows the economies of scale that the enterprise networks are gaining through "cloud compute" to the telco space, by implementing these traditionally custom hardware based elements (such as media gateways, firewalls, SBCs, Routers, CSCFs) in standard (commodity Servers) architecture servers and a hypervisor layer, utilising the same virtualisation tools which enable flexibility of deployment of these elements in more standard environment, enabling features such as live migration of network functions under failure, multiple instances of a network function on the same hardware elements, and more interestingly (from my perspective) the ability to create multiple instances belonging to different customers (or even carriers) on the same hardware platforms.

Time to re-write the architecture rule book.

Friday, 20 September 2013

IPTV & 4G Apps (continued from previous post)

I've just been reading that Alcatel Lucent have received an Emmy for their Cloud PVR ( Its a nice idea and the logical extension of the home based PVR, or the SlingBox, and their concept of placeshifting (aka watch anywhere).

The slingbox and the Alu Cloud PVR share the same idea - watch linear TV as you like it, time shifted and from any location on any device. These two are not the only kids on the block Virgin are offering similar service with their TV Anywhere pitch.

So what's the point and what's the link with these services and 4G. Obvious really 4G (LTE and LTE-A) gives the means of distribution and the data rates to do it. The roll out of fibre to the kerb and the home around the world (it FTTC in the UK mostly) gives the uplink from the Home to use your STB to consume content anywhere, LTE to pull it down. Tablets have provided the device to consume the content on. The benefit of the Cloud PVR is of course - no need for the high speed up from your home. The downside from the carriers perspective is they still need sufficient tuners in the network (head-end) to be able to cope with all the simultaneous channels customers want to record.

So the big question that's been burning in my brain: Why do we need IPTV combined with IMS? (Ala TISPAN standards), my current thinking brings me to the conclusion - We don't.

The future of the cloud enabled telco is on everyones hot topics at the moment and I think I can see a "continental drift" scale change happening in network architecture design, the move from circuit switched to packet switched was the start - so called "cloud" architectures will now also impact heavily the way we design and build future networks and hybrid architectures that build the best of both the older telco design principles and the more "Internet" view of design (centralised vs. distributed compute intelligence) are evolving.

Thursday, 19 September 2013

The Network is the call(c)

Some years ago Sun microsystems had the the strapline the "The network is the Computer". I came up soon after that with the phrase "The network is the call"(c), at the time in reference to the migration from traditional TDM based telephony networks to Voice over IP (VoIP) or Telephony over IP (ToIP).

Having just discovered I think the phrase now has even more meaning when linked with Social Media and WebRTC.

In my previous post I started discussing Over The Top (OTT) services and their relevance and threat to the traditional carrier model, and whilst we (carriers, standards bodies and consultants - me included) think about how we maintain quality of service and preserve the five-nines nature of telephony networks, we miss the point. Interaction between people needs to be spontaneous, easy and unrestricted. In some instances the restriction is not a physical impediment such as ease of use.... Its money. I've just recently been hit by additional charges on my mobile phone that are greater than my "so called inclusive package". When I queried this, it was 0844 (PowWow) conference number from a couple of conferences I took part in. Having just suffered "bill shock", I will avoid using my mobile for these services and found the great app "sayno to 0870" and website of the same name.

Applications of WebRTC such as the twelephone are a great example of how a service can change both my "traditional" view of communications and my behaviour. Even without all the heavy overhead involved in solving a QoS problem which (even on the Internet via my ADSL) isn't there.

I'd like to thank John Gage for "The Network is the Computer" and hope my version "The Network is the call"(c) helps to change other people's view of how telecommunications now is being shaped by the "Internet generation".

Tuesday, 10 September 2013

IPTV & 4G Apps in an IMS Core - what next for App Store and IPTV?

I was recently reading the Netflix view of the future of television and it set me thinking, as these things often do. Netflix's opening gambit in their "Long Term View" is that Linear TV's days are numbered. For those who aren't familiar with the terms, Linear TV is where you watch a set of channels with a broadcast schedule - i.e. programming follows a linear timeline, once a programme's allotted slot (in time) has gone, you missed it. This represents pretty much what all of us currently experience as terrestrial or satellite TV, without the use of a Personal Video Recorder (PVR).

How a lot of us consume TV now is a mixture of linear programming - augmented with a PVR so the linearity is - well none-linear! For those hooked on reality TV and more than that live reality TV the linear model still works - IF you add interaction from the audience, not to mention of course sporting events - that are probably the mainstay of linear broadcasters. So whilst I have to agree with Netflix's view about the decline of linear TV (heck most of us using a PVR aren't linear any more anyway), its difficult model to break especially in the UK where we have a pretty good terrestrial broadcast TV network.

The terrestrial broadcast TV model when the coverage is as good as it is in the UK is a difficult one to break.... Or is it? With the advent of Digital Video Broadcast - Terrestrial (DVB-T - Freeview/Saorview/La Télévision Numérique Terrestre (TNT) - or whatever it is called in your part of the globe), we get the same originally channels and guess what even more to watch (well if you can find a programme worth watching - then you'll probably record it!) Think about this for a moment.... What do we actually have here..... A nationwide Digital Broadcast medium capable of transmitting multiple video and audio streams, simultaneously with the customer requiring nothing more than a relatively inexpensive roof (or loft) mounted antenna, and receiver capable of translating that in to the image we see on the screen. What's more - the way the channels are transmitted (a MUX/virtual subchannel/bouquet as it is called), means we now have multiple programmes/stations per frequency, more than this - these "channels" are also capable of carrying data in the form of MHEG-5 or the Java based Multimedia Home Platform (MHP). Combined with faster internet access for a "back-channel" uplink communications path for these Xlets (Set-Top-Box Applets), in theory you have a recipe for Set-Top-Apps........... Which vendors of STB and DVD/Blueray players are starting to adopt.

Well almost of course we now See Internet enabled TVs. Blueray players and STBs, with embedded apps for Netflix, Lovefilm and the linear TV programmer's Apps (Like the BBC iPlayer, ITV Player and Demand5 and the like). These use HTTP streaming to create a none-linear model for consumption of content, built on the success of their Internet (PC/Mac/Browser and Tablet) variants. The limiting factor for these "apps" is available bandwidth from the Broadband connection. Whilst this is steadily improving, its still not what it could be everywhere (that's a whole other discussion right there!) The point I am moving towards - is better integration of these apps within the STB with the DVB data service and channel guides, and of course core network services.

We've long discussed (in the telecoms industry) the utopian view of telecommunications services that are fully integrated with our Diary and calling behaviours and to some degree we're there - well at least the technology is getting there to support it with the IMS-OSA Application Servers standardised and a Java Specification for device interaction with the IMS (JSR180 and JSR281). JSR281 as an interesting specification - designed as part of the embedded Java platform - Which MHP is exactly that - in an STB! So we have a mechanism for interacting with IMS services from and STB or "Internet TV", this allows us to initiate a multimedia session, combined with the DVB-T broadcast capability for distribution of video content nationally (at least) we have a recipe for building interactive services. However.... Carriers are still deploying or are "to" deploy IMS for mobile environments and are currently still in transition or at best mixed network environments for fixed, not to mention this disparity of xDSL provision in a competitive market and the mobile operator's current fixation of LTE rollouts. Some carriers are rolling out IPTV services combined with DVB-T receivers to combine, Linear, Near Video-On-Demand (NVoD) and Video-On-Demand (VoD) services.

What does the above paragraph mean? Well at the moment the market is at best fragmented and the current winners are the Over-The-Top (OTT) providers, the likes of the BBC, Lovefilm and Netflix. These providers are "piggybacking" on the Mobile and Fixed provider networks (data) and delivering content using STB apps. The IMS and OSA App Server and JSR281 mechanism may well be a redundant set of standards...... Is there a future for IPTV and IMS marriage as proposed in the TISPAN standards... I'm going to stick my neck out here and say "NO". In my humble opinion (IMHO) that horse has bolted - so to speak. OTT applications as cited above are in my mind more likely to succeed.

Note: OTT is clearly on Genband's mind too:

Offering the Fring white label service to carriers is an interesting step.

Is Linear TV and more specifically DVB-T services dead... Not yet, and IMHO I think have a life beyond the Set-top box - why - because they're (compared to Internet TV) cheap to distribute programming in infrastructure terms. Whilst we can rollout IP Multicast to "trim" the distribution of media streams, Linear plus PVR wins easily.

(More to come -whilst I chew on this topic a little more in my head) 
Next the question of IP Stores for Set-Top-Boxes and Internet TVs. Google (Android) and Apple (Apple TV) and Microsoft want to own this.... What about the Network Operators rolling out LTE data services... They'll want piece of the actions too............ Maybe even WebRTC is the answer?

Saturday, 31 August 2013

SIP trunking - interesting how much is involved when you sit down and think!

I've recently spent a little over 3 days working on a new set of training material on SIP Trunking as part of my Wraycastle work. It amazing how much you hold in your head about topics. It's only when you start to put "pen to paper" so to speak that you realise there's a lot more about a topic than you superficially had in the front of your mind.

It turns out 33 slides later there is actually a great deal more than the SIP Forum's SIPConnect 1.1 specification when you start to consider all the facets of SIP trunks in their broadest sense, i.e. both Carrier to Carrier - Network to Network Interface (NNI) and Carrier to customer - User to Network Interface (UNI).

From a customer /Enterprise view-point I can see two main scenarios playing out:

Existing TDM PBX where the customer doesn't want to upgrade to a new IP-PBX, so chooses the media gateway route to terminate a carrier SIP interconnection with their TDM PBX.

And Scenario two where a customer has invested in the IP-PBX or Unified comms platform and builds a separate network and connection for their voice infrastructure.

I then went on to consider the following areas:

•Why SIP Trunking
Brief market look at SIP trunking – why customers are moving from PRI to SIP trunks
Carriers Perspective Why SIP trunks make sense

Customer Scenarios
  • E-SBC and IP-PBX Interconnect
  • VoIP Gateway to Traditional PBX (AudioCodes, Sonus, Cisco CUBE)
  • Multi-site
  • IP-PBX or Microsft Lync
  • Contact Centres (Queue-ing – SIP Response 182 Call Queued)
  • Emergency Services access

•Carrier Scenarios
• Example TalkTalk Business & Virgin Media Business, BTWholesale IPVoice and IPExchange
• Emergency Services Provision

Technical standards and overview of delivery
What a SIP trunk in technically (SIP Forum Standard – SIPConnect)
Design Options from a carriers perspective
Authentication (IP address based vs. SIP Registrations, SSL SIPS and SRTP)
Transcoding, Codec Support
Session Management
SIP interworking with ISDN (Q.931, Q.SIG – RFC4497 - rfc4497)
QoS monitoring

Gotchas – 
Point Of Sales devices,
Franking machines 
and Alarm systems
Multisite and Bursting
CAC and capacity planning
Optimal Routing (REFER and 302 Redirect, vs 486 Busy and 603 Decline)
Site Failure (detection) 
and redirection (SIP OPTIONS messages)
Security Considerations (SPIT – SPam over IP Telephony)

If anyone is interested in knowing more about any of these areas - or even the whole course, then contact Wraycastle - you'll find them at:

Saturday, 27 July 2013

WebRTC - LTE - Over The Top (OTT) services and disruption - or opportunity?

I've recently been looking hard at IMS and LTE - as both these technologies are finally gaining traction in the market place with Carriers upgrading their networks to 4G with VoLTE to follow very soon - within a year or so for many.

I've also been closely following the rapid rise of WebRTC and its deployment in browsers, Firefox and Google Chrome on you desktop now support WebRTC APIs and very soon it will be on your smartphone (

Carrier vendors such as Genband and others are all ready with their implementations of App servers capable of providing WebRTC.

There is plenty of support in the Open Source community with Asterisk, Freeswitch and Kamailio and OpenSIPs support SIP over websockets and OverSIP ( and the sipML5 HTML5 (Javascript SIP/SDP stack)... Not to mention MobiCents Open source IMS app server's support for it (

More Interesting on this front as well is the recently announced Project Clearwater ( IMS in the cloud.

It seems to me there is about a 1 year opening for the Over The Top providers (OTT) to get in on LTE and capitalise on the carrier's reluctance to use VoLTE. Its not to say there won't be issues - carrier's LTE implementations will probably be restricted to a single Data service offering for this first year, offering Dongles and WiFi Personal hotspots (MyFI) over a none QoS bearer service, which might not be the best for offering voice and video services (but that doesn't stop most of us using Skype!)

From the carriers perspective it might also be worth considering their position with respect to partnerships to enable OTT providers or deep packet inspection technologies to block the OTT vendors from utilising WebRTC applications. Partnership in my mind is better for both. It gives OTT providers the opportunity to get a QoS bearer service for their applications (QCI 5 and QCI 1 EPS Bearers) and potentially a custom APN to support this. For the Carriers innovation has not historically been a carrier's strength - partnership brings the opportunity to gain revenue from innovative services with little or no cost of development, and prevents them from the constant fear of becoming a bit-pipe provider only.

Whilst thinking about QoS/QoE it also struck me that its going to be a bit more tricky (not impossible) for 3rd party QoS/QoE software probes to monitor the Quality of Web RTC traffic, on two counts, 1) its peer to peer - unless forced to be otherwise (media anchoring); 2) the media and RTCP is "munged" (technical term) together into a single UDP stream to improve on the chances of successful NAT traversal. And on a third count - the media may also be encrypted.

Wednesday, 17 July 2013

VMWare of Microsoft HyperV - Free or Licenced?

Whilst considering the design requirements of a hosted contact centre solution, one of the requests has been to consider which elements can be considered for virtualisation. The products in question for consideration are Oracle CallCallCenterAnywhere (CCA) and Cosmocom Call Universe (CCU).

Oracle CCA is officially end of life and now in extended support from Oracle - this doesn't stop people using it though and both my self and a number of consultants are still supporting this platform, testament to the guys at Telephony@Work who created this great product and shame on Oracle for end-of-life for the product. Fix Pack 10 supports Windows server 2008 - 32 bit only officially however the small print in the release notes indicates the executables have been tested to run on 64-bit Linux. This means there at least is the potential to support both HyperV and VMWare hypervisors.

That said the Cosmocom Call Universe product is now the only real alternative for multi-tenant host (Carrier scale) Contact Centre platform and thanks to the continued support and development fully support virtualisation. (footnote: I'm hoping for big things from Genesys Labs with their new cloud offering in this space).

Both CCA's and CCU's architecture support redundancy in their design, which means technologies such as live migration/vmotion are redundant in some respects for per data centre availability. However with 2 data centres the option for "WAN" live migration opens up the potential for a higher availability of the elements. This point requires careful consideration of the options. Since the other options open to is is just databased replication across the WAN to keep items in sync.

Having spent some time assessing VMWare vs. HyperV and product support of these hypervisors from Cosmocom - VMWare wins. Primarily on known to work on ESXi hypervisor, since CCU is currently only tested on Windows server 2008 with HyperV role. And secondary consideration is the footprint of the hypervisor with the the VMWare being a real light weight at around 512 Meg RAM!

Tuesday, 19 March 2013

Wow... Its been a bit mad this year, since finishing a contract at News International, its been all go hitting the books again teaching with Wraycastle. I've spent February and March travelling back and forth to Holland, Southern Ireland and around the UK, teaching TCP/IP, VoIP/IMS and MPLS courses.

I've been working hard upgrading my Cisco Lab and added 6 3725 routers, 2x 2950 switches (one which seems to be a survivor of a skip dump!) and a Cisco Catlyst 3550 layer 3 switch. This lab together with GNS3 and 8G RAM on my laptop and Mac Mini has helped me craft some pretty cool lab set-ups for demonstrating and teaching OSPF, BGP, MPLS, MPLS VPNs, Ethernet Over MPLS (and VPLS) and MPLS-TE.

I'll get around to posting some lab work hopefully in the next couple of months.. One that would be great to get going Pseudo Wire carrying an E1 (30 channel) voice circuit.

More anon......