Showing posts with label Cisco. Show all posts
Showing posts with label Cisco. Show all posts

Monday, 26 September 2016

QoS in VoWiFi

Came across this presentation by Eir from last year's LTE Voice Summit.

As the summary of the above presentation says:

  • Turning on WMM (or WME) at access point provides significant protection for voice traffic against competing wireless data traffic
  • Turning on WMM at the client makes only a small difference where there are a small number of clients on the wireless LAN. This plus the “TCP Unfairness” problem means that it can be omitted.
  • All Home gateways support WMM but their firmware may need to be altered to prioritise on DSCP rather than layer two

As this Wikipedia entry explains:

Wireless Multimedia Extensions (WME), also known as Wi-Fi Multimedia (WMM), is a Wi-Fi Alliance interoperability certification, based on the IEEE 802.11e standard. It provides basic Quality of service (QoS) features to IEEE 802.11 networks. WMM prioritizes traffic according to four Access Categories (AC): voice (AC_VO), video (AC_VI), best effort (AC_BE), and background (AC_BK). However, it does not provide guaranteed throughput. It is suitable for well-defined applications that require QoS, such as Voice over IP (VoIP) on Wi-Fi phones (VoWLAN).

WMM replaces the Wi-Fi DCF distributed coordination function for CSMA/CA wireless frame transmission with Enhanced Distributed Coordination Function (EDCF). EDCF, according to version 1.1 of the WMM specifications by the Wi-Fi Alliance, defines Access Categories labels AC_VO, AC_VI, AC_BE, and AC_BK for the Enhanced Distributed Channel Access (EDCA) parameters that are used by a WMM-enabled station to control how long it sets its Transmission Opportunity (TXOP), according to the information transmitted by the access point to the station. It is implemented for wireless QoS between RF media.

This blog post describes how the QoS works in case of WMM.

Finally, this slide from Cisco shows how it will all fit together.

Further reading:

Friday, 19 July 2013

Nice way of showing HetNets, by Cisco #LTEWS

This is from a presentation by Akram Awad of Cisco in the LTE World Summit 2013 in Amsterdam. I really like the way HetNets are explained

Saturday, 1 December 2012

Data growth from 0.6EB/Mo to 10.6EB/Mo by 2016 (18x)

A slightly old slide that I found while looking for some information but worth putting up here.

1 EB (Exabyte) = 1000000000000000000B = 1018 bytes = 1000000000gigabytes = 1000000terabytes = 1000petabytes

As we can see, Cisco predicts (and I agree) that the mobile data consumption will increase from 0.6 exabytes per month to 10.6 exabytes per month by 2016. What is really debatable is what actually is a mobile device and how much of this data will go through the operators network.

If for example a tablet contains SIM card but you use your own home/work WiFi. Does this qualify as a mobile device and is this data included. What if its exactly the same scenario and the device does not have a SIM card then would you say this is a mobile device? What happens when the operator allows you to use an Operator WiFi which is secured via login/password and you use the tablet without SIM card on an operator WiFi. Would you count this data, is the device considered as a mobile device.

The bottom line is that data usage will continue to grow but probably not on the mobile networks. WiFi would be a prime candidate for offloading, due to it being mostly free (or costing much less - except in the hotels). Some of the recent pricing by the operators make me feel that they do not want the users to use their network for every day use, only for important work.

See Also:

Friday, 16 November 2012

Evolution of 'Internet of Things' to 'Internet of Everything' #IoE

Will the 'Internet of Humans' and the 'Internet of Things' (IoT) evolve into 'Internet of Everything' (IoE). This is certainly what Dave Evans, the Cisco Futurist thinks. This is from his blog:

From the Internet of Things (IoT), where we are today, we are just beginning to enter a new realm: the Internet of Everything (IoE), where things will gain context awareness, increased processing power, and greater sensing abilities. Add people and information into the mix and you get a network of networks where billions or even trillions of connections create unprecedented opportunities and give things that were silent a voice.

As more things, people, and data become connected, the power of the Internet (essentially a network of networks) grows exponentially. This thinking (“Metcalfe’s law”) comes from Robert Metcalfe, well-known technologist and founder of 3Com, who stated that the value of a network increases proportionately to the square of the number of users. In essence, the power of the network is greater than the sum of its parts, making the Internet of Everything, incredibly powerful.

You can read more here.

See Also:

Saturday, 13 October 2012

Imagine the Future - by Cisco

Here is a video from Cisco from the last year, that I think is still relevant to help put in perspective where the future is going:

There is also a slide cast worth watching on the same topic from last month:

Monday, 3 September 2012

Cellular or WiFi: Which is the preferred network access?

I was going through this report by Cisco on "What do Consumers want from WiFi" and came across this interesting picture. 

With the ease and availability of easy WiFi, it would be the preferred access technology whenever possible. Cellular access would be generally reserved for mobility scenarios or where there is no wifi network to allow access.

Another interesting observation from above is that the survey puts WiFi and Cellular security to the same level. Though the cellular is more secure in case of an open public WiFi scenario where an eavesdropper may be able to get hold of login/password information it is generally at the same level of security to a secured WiFi. On the other hand with cellular, lawful interception may be much more easy as compared to using secure WiFi.

I am sure that the content of last paragraph are debatable and am happy to hear your viewpoints.

A slidecast of the Cisco whitepaper mentioned above is embedded as follows:

Tuesday, 24 April 2012

LTE and IPv6

A discussion on Linkedin prompted me to add some relevant documents relating to LTE and IPv6. Interesting presentation below by Cisco:
Designing LTE with IPv6
View more presentations from Zahid Ghadialy. Available to download from slideshare here.

There are some other interesting presentations on slideshare you may want to look at:

Monday, 18 July 2011

Infographic on 'The Internet of Things'

Very interesting Infographic from Cisco on the 'Internet of Things' that we have discussed before.

Since its not possible for me to put the whole Infographic here, you can check it out on Cisco blogs.