Monday, February 14, 2011

Hotspot Advancements Signal Wi-Fi Evolution

Multiple announcements of advanced Wi-Fi hotspot capability have been announced in the past week during the lead up to Mobile World Congress 2011. These announcements signify a significant effort to provide Wi-Fi hotspots that are easier to use, provide advanced capabilities, and can integrate with broader cellular mobile networks.

Cisco announced their MOVE Strategic Framework, which incorporates Service Provider Wi-Fi. Ruckus announced a Wireless Services Gateway for integration of back-end Wi-Fi and Cellular management and billing. Earlier this week, Nokia announced Smart WLAN, a software package aimed at automating roaming between cell and Wi-Fi networks. And finally, the IEEE 802.11u amendment is scheduled for final approval this month to provide standards-based advanced hotspot capabilities and inter-working with external networks.

I've written numerous times about the proliferation of Wi-Fi hotspots (including AT&T managed hotspot service), the growing need for cellular network operators to offload data from overburdened 3G networks, the growing importance of mobile commerce and marketing (especially with the Mobile Retail Initiative), Wi-Fi hotspots as a medium for consumer interaction, and the importance of the IEEE 802.11u amendment in integrating cellular and Wi-Fi networks.

Why are these announcements important? Because they signify that the Wi-Fi industry has turned a corner. No longer is Wi-Fi being regarded as the ugly unlicensed spectrum step-child of much larger licensed spectrum networks. The realization that Wi-Fi is important as a complementary service to cellular mobile networks has sunk in. Wi-Fi can provide localized capacity growth sufficient to meet surging mobile data usage, and this strategy has now permeated carrier roadmaps to the point that the leading Wi-Fi market vendor has responded. In addition, retailers are clamoring to better engage customers where they have the most influence, in-aisle through mobile advertising. The lack of sufficient indoor cellular penetration coupled with the high expense of cell repeater and DAS solutions, and immature femtocell solutions are driving retailers toward Wi-Fi hotspot deployment.

These announcements are more about industry innovation and service integration capabilities (what Cisco calls Hotspot 2.0) than about incremental hardware improvements.

Cisco has done a nice job capturing the requirements needed for Hotspot 2.0 in this whitepaper just released. It's important to note, that while this announcement is geared toward mobile network operators, it is equally applicable to privately operated hotspots by independent establishments such as retailers, municipalities, educational institutions, and others.

Hotspot 2.0 Drivers:
  • Growing Mobile Data Demand
  • Economic Benefits of Offloading Mobile Data from Cellular to Wi-Fi
  • Usability Problems of Today's Wi-Fi Hotspots
  • Security Threats of Open Wi-Fi Hotspots
Hotspot 2.0 Solutions:
  • Selective IP Traffic Offload (Carrier Core Network vs. Public Internet)
  • QoS Preservation
  • Improved End-User Experience on Wi-Fi Hotspots
    • Automated Network Selection, Authentication and Roaming by Devices (not Users)
    • Flexible Authentication Options to Support Multiple Devices and Roaming Agreements
    • In-Band Account Provisioning
    • Network Type Advertisement (private, free public, paid public)
    • Network capability advertisement through the new layer 2 protocols (GAS and ANQP; similar to EAP where the access point acts as an intermediary proxy between client and server)
  • Service Advertisement and Monetization through MSAP (Mobility Services Advertisement Protocol)
However, some very big outstanding questions remain:
  • Infrastructure Availability of Hotspot 2.0 Functionality
  • Mobile Device Availability of Hotspot 2.0 Functionality
  • Reduction of Handset and Carrier Implementation Variances
  • Independent Network Operator Integration with Carrier Networks (via roaming agreements, etc.)
There is still a long way to go to realize advanced Wi-Fi hotspot services and seamless integration of cellular and Wi-Fi networks, but this is a great step in the right direction!

Wi-Fi is truly growing beyond its roots, from best-effort to mission critical, from private to public networks, from indoor to outdoor, and from isolated networks to large-scale integrated access networks. It's my firm opinion that "Hotspot 2.0" will prove to be a significant evolutionary milestone for Wi-Fi as a technology.

Come, share my excitement!


Sunday, February 13, 2011

Bookmarklets for Mobile Devices

I read a lot of news and like to share a lot of it with friends, family, and professional networks using various services on the web. The easiest way for me to collect, consume, and distribute this content is through social media services such as Google Reader, Twitter, Facebook, and Email. 

I'm also always on the go, and it's increasingly rare that I can devote enough time during the week in front of a traditional computer or laptop to read all the news, information, and stay up to date as much as I want to. Therefore, it's an easy investment for me to own a smartphone to consume content whenever I have a minute or two of downtime. This makes information consumption much easier and fits better into my schedule. I also recently purchased a tablet to fill the intermediate gap when the screen size of a smartphone just isn't suitable for some content, but a tablet is still portable enough to carry with me most of the time. 

However, transitioning from a full web browser (Chrome is my preference) on a laptop, to a mobile browser (Safari on my iPhone/iPad), has caused some challenges. Normally, I find quite a bit of content that is shared by others through any one of the aforementioned services, which I want to subsequently re-share or post to my social networks. In Chrome, I use Bookmarklets to accomplish this task. Bookmarklets are simply small bookmarks comprised of javascript code that performs a specific function with the content in the current browser window. For instance, the Google Reader bookmarklet allows adding, sharing and note creation of items into your Google Reader feed.

Many of these bookmarklets are provided as links in webpages, allowing full browsers such as Chrome to easily drag and drop the link into the bookmark panel. However, mobile Safari does not allow direct bookmarking or copy/paste of these javascript links.

Therefore, I have copied out the javascript contents of these links in order to install these bookmarklets in mobile Safari. The process is fairly simple:
  1. Copy the bookmarklet URL javascript contents from a desktop browser (or use my favorites listed below)
  2. Email the contents to yourself
  3. Open the email on your mobile device
  4. Copy the javascript content from the email
  5. Open mobile Safari
  6. Create a new bookmark while on any page
  7. Edit the bookmark, name it appropriate to the service, and paste in the javascript in the "Address" section
Now, when you're browsing any content that you want to share, click the appropriate bookmarklet from the bookmark menu and the service will prompt you to edit/send the item.

Here are some of my favorite bookmarklets:

Hootsuite Post
javascript:var d=document,w=window,f='',l=d.location,e=encodeURIComponent,p='address='+e(l.href)+'&title='+e(d.title),u=f+p;a=function(){if(!,'t','scrollbars=0,toolbar=0,location=0,resizable=0,status=0,width=550,height=330'))l.href=u;};if(/Firefox/.test(navigator.userAgent))setTimeout(a,0);else a();void(0);

Hootsuite Post (launch iOS application)

Google Reader Note
javascript:var b=document.body;var GR________bookmarklet_domain='';if(b&&!document.xmlVersion){void(z=document.createElement('script'));void(z.src='');void(b.appendChild(z));}else{}

Instapaper Note
javascript:function iprl5(){var d=document,z=d.createElement('scr'+'ipt'),b=d.body,l=d.location;try{if(!b)throw(0);d.title='(Saving...) '+d.title;z.setAttribute('src',l.protocol+'//'+encodeURIComponent(l.href)+'&t='+(new Date().getTime()));b.appendChild(z);}catch(e){alert('Please wait until the page has loaded.');}}iprl5();void(0)

Facebook Post
javascript:var d=document,f='',l=d.location,e=encodeURIComponent,p='.php?src=bm&v=4&i=1265501632&u='+e(l.href)+'&t='+e(d.title);1;try{if (!/^(.*\.)?facebook\.[^.]*$/.test(;share_internal_bookmarklet(p)}catch(z) {a=function() {if (!'r'+p,'sharer','toolbar=0,status=0,resizable=1,width=626,height=436'))l.href=f+p};if (/Firefox/.test(navigator.userAgent))setTimeout(a,0);else{a()}}void(0)

Gmail Message
javascript:popw='';Q='';x=document;y=window;if(x.selection) {Q=x.selection.createRange().text;} else if (y.getSelection) {Q=y.getSelection();} else if (x.getSelection) {Q=x.getSelection();}popw ='' + escape(document.title) + '&body=' + escape(Q) + escape('\n') + escape(location.href) + '&zx=RANDOMCRAP&shva=1&disablechatbrowsercheck=1&ui=1','gmailForm','scrollbars=yes,width=680,height=510,top=175,left=75,status=no,resizable=yes');if (!document.all) T = setTimeout('popw.focus()',50);void(0);


Friday, February 11, 2011

Article Round-Up: 02/11/2011

Here are a collection of Wi-Fi related articles that I have found useful, interesting, or enlightening. As always, for a complete list of articles check out my shared article feed from Google Reader.

My Stuff
General Wi-Fi Articles
Retail Wi-Fi / Mobility Articles
  • JCPenney is integrating iPads in-store for increased customer influence.
  • Nordstrom sees their business evolving from customer-focused to customer-driven by excelling at e-commerce, multi-channel, and improved customer experience in-store through Wi-Fi.
  • InformationWeek talked about how Location Based Services are driving customer store visits and influencing purchase decisions. LBS will evolve from GPS style navigation and check-ins to in-store product search and promotions over RFID and Wi-Fi. Be prepared.
  • While we're on LBS, check out NearBuy's Micro-Location Solution.
Comic for the Week!

Cheers (and happy reading)!

Friday, February 4, 2011

Cisco Unified Wireless Network Ports

Here is a reference for the well-known Cisco Unified Wireless Network ports. This list is handy as a reference when creating firewall and security rule-sets, as well as for protocol analysis, decoding session and stream conversations, troubleshooting, and studying for various certification exams.

Cisco Unified Wireless Network Ports

LWAPP Data Packets: UDP 12222
LWAPP Control Messages: UDP 12223

CAPWAP Control: UDP 5246
CAPWAP Data: UDP 5247

WCP for WiSM: UDP 10000

Mobility Control Messages: UDP 16666 and/or UDP 16667 (secure-mode)
Mobility EoIP Tunnel: IP Protocol 97

RRM Messages 802.11b/g Client: UDP 12124
RRM Messages 802.11b/g Server: UDP 12134
RRM Messages 802.11a Client: UDP 12125
RRM Messages 802.11a Server: UDP 12135

Radius Authentication: UDP 1812
Radius Accounting: UDP 1813
Radius Authentication (legacy): UDP 1645
Radius Accounting (legacy): UDP 1646


DHCPv4 Clients: UDP 68
DHCPv4 Server: UDP 67
DHCPv6 Clients: TCP/UDP 546
DHCPv6 Server: TCP/UDP 547

Telnet: TCP 23
SNMP: UDP 161 and UDP 162
Syslog: UDP 514
NTP: UDP 123


Well-Known Cisco WLAN Intervals

Knowing the interval at which major important functions occur within a wireless network is an important aspect when designing a network for optimal performance as well as when troubleshooting problems.

Jeremy Stretch has started a Well-Known Intervals wiki page on to organize a community resource around this topic. Below, you will find a list of the most common and important timers for Cisco wireless networks, both Unified and Autonomous. I will be contributing these intervals for inclusion on Jeremy's wiki page.

Note that most (but not all) of these intervals are defaults, and can be changed through administrator configuration.

  • 102.4 ms 802.11 Beacon Period (WLC and Aironet IOS)
Unified Wireless Network (7.0 Code Version)
  • 1 sec EAP-Identity-Request Timeout
  • 1 sec EAP-Request Timeout
  • 1 sec EAPOL-KEY Timeout
  • 1 sec CleanAir AP Sampling Interval
  • 2 sec RADIUS / LDAP Server Timeout
  • 2 sec NMSP Updates from WLC to Loc/MSE Server
  • 10 sec 802.1x Supplicant Response Timeout 
  • 10 sec Mobility Keepalive Interval
  • 10 sec AP Discovery Timeout
  • 15 sec CleanAir AP AQI Calculation Interval
  • 20 sec WCP Keep-Alive Timer (WiSM/Cat65k/3750)
  • 30 sec AP Heartbeat Timeout 
  • 1 min RRM Neighbor Packets 
  • 1 min CCX Location Measurement 
  • 1 min Client Exclusion 
  • 1 min IGMP Snooping Timeout 
  • 90 sec Traffic Stream Metric Reports 
  • 2 min AP Primary Discovery Timeout
  • 3 min RRM Off-Channel Scanning Sweep Time
  • 5 min Client Idle Timeout 
  • 5 min ARP Timeout 
  • 5 min RADIUS Fallback Interval 
  • 5:20 min WCP Keep-Alive Timeout & Module Reboot (WiSM/Cat65k/3750)
  • 10 min RF Group Update Interval 
  • 10 min RRM DCA Channel Update Interval 
  • 10 min RRM TPC Power Update Interval 
  • 15 min CleanAir AQI Reporting Interval 
  • 20 min Rogue Entry Timeout 
  • 30 min Client Session Timeout 
  • 1 day WLC Local Guest User Account Lifetime 
  • 7 days CleanAir Persistent Device Avoidance Interval 
Autonomous Wireless Networks
  • 2 sec RADIUS Server Timeout 
  • 30 sec 802.1x Supplicant Response Timeout 
  • 1 min Client Idle Timeout 

Tuesday, February 1, 2011

The State of Voice over Wi-Fi

I recently read this article on PC World by Jason Kennedy, "Wi-Fi Calling: T-Mobile's Unused (So Far) Ace in the Hole", which got me thinking about the overall state of Wi-Fi calling in general.

Here's how I see the Voice over Wi-Fi (VoFi) landscape right now:

Enterprise VoFi
A broad array of product offerings are available, including Polycom (SpectraLink), Cisco, Avaya, Microsoft, Vocera, and others. The overall state of IP-PBX deployment is fairly broad and definitely mature. At this point, I would hard-pressed to find a medium to large enterprise that hasn't begun a migration from analog TDM or digital voice to a VoIP solution. Hospitals seem to be the standout industry, deploying Vocera badges for hospital staff like crazy.

At the lower end of the spectrum, SMBs, educational institutions, and many small state and local government entities are probably still running off fairly old (ancient?) analog / digital systems. But hey, with minimal budgets they have to prioritize and I can't fault them for not wanting to spend money on replacing a working telephony system that probably cost them a fair penny in investment on a PBX or key system.

Voice over Wi-Fi adoption is not as widely deployed and is commonly seen as a nice addition to an existing VoIP network, but not an immediate requirement. As user mobility within the enterprise increases, especially with broader consumer demand of desk phone portability (laptop soft-phones, tablets, dual-mode phones), VoFi adoption can be implemented fairly easily once the leap to VoIP has been made. The largest hurdle facing most deployments will be proper WLAN design for VoFi, which may require adding experienced wireless engineers to the staff or hiring out the work to a 3rd party integrator.

Cellular / Telco VoFi
The long-hyped FMC (Fixed Mobile Convergence) that would allow seamless voice call hand-over between Wi-Fi and cellular networks is still not widely deployed. Only minor installations with well justified business benefits and ROI have seen adoption. The good news is that this slow-start has allowed the technology to mature, and it is remarkably ready for broader enterprise use.

T-Mobile has clearly been the leading telco adopter of VoFi with their UMA solution for enterprises. Additionally, support for consumer deployments came with their Hotspot@Home feature back in 2007. At $10 a month, it was a steal for consumers needing additional coverage in weak cellular areas, needed to reduce used minutes, or used a very large number of minutes each month. And it worked pretty well. However, support was fairly short-lived and the feature was canned last year in April 2010.

However, their back at it, having recently announced a partnership with Cisco to  provide seamless voice roaming between enterprise Wi-Fi networks and cellular networks. And at their Investors Day in January they announced that all of their Android and Blackberry smartphones support Wi-Fi calling. It's still unknown if other U.S. carriers see T-Mobile's Wi-Fi / UMA service offering as a threat and will follow suit with FMC solutions. However, support of Wi-Fi in general by cellular carriers is definitely growing exponentially, with Verizon and Sprint offering portable 3G/4G Wi-Fi hotspots and AT&T deploying managed Wi-Fi hotspots wherever it can ink a deal (and pick corporate pockets?).

Consumer VoFi
On the consumer side, offerings have been out on the market for a while. Skype has been the primary adopter in this space, having partnered with La Fonera as early as 2006 to offer Wi-Fi calling. Vonage also offers limited support for Wi-Fi calling, but has been hampered by poor financial performance preventing broader investment in the solution.

Newer entries into this space have been provided by smartphone application developers taking advantage of advanced feature capabilities of newer Apple and Android smartphone operating systems. Line2, Fring, and Talkatone are all examples of apps that make VoFi calling on smartphones a reality for incredibly cheap, especially when paired with VoIP services such as Google Voice or Skype.

However, mass-market consumer awareness of such options still remains thin. Adoption has been limited to tech-savvy consumers or individuals stumbling across such services while researching foreign travel options.

My Take on VoFi
Enterprise VoFi is mature and poised for mass deployment. Enterprise IT departments have wrapped their arms around VoIP networks over the last decade, and extension of VoIP onto the Wi-Fi network will require minimal effort. However, proper WLAN design, testing, and verification should not be overlooked, as traditional wireless data network deployments are often ill-suited for VoFi. The push by employees for greater mobility and desk phone portability will also drive demand for VoFi.

Carrier FMC voice hand-over between cellular and Wi-Fi is maturing rapidly and ready for broader use. However, business justification and clear ROI for most organizations is still hampering its adoption. Don't expect this to change overnight. It will be interesting to see if real-time video calling (such as Apple's FaceTime) will have any impact on enterprise FMC adoption. We'll just have to wait-and-see.

Consumer VoFi solutions are available for individuals savvy enough to take advantage of them, and they can save a few bucks doing it by shaving cellular bills. They can also gain better voice quality and coverage inside homes and locations with poor cellular reception. However, until a major proponent of Internet voice service with a user base that can bring their solution to the forefront emerges, adoption will remain limited. Watch for newcomers to differentiate themselves from traditional telco landline and cellular providers by offering a broader set of features and controls for consumers. Google appears to have all the pieces to make this happen, if it chooses.

Let's not forget that the adoption of 802.11n Wi-Fi is already playing a part in these solutions, offering better network performance and rapidly changing the perception of Wi-Fi capabilities.

I'd love to hear your feedback on VoFi adoption.
  • What is your organization doing with VoFi for internal calls?
  • Has your organization explored FMC? What decision points justified (or failed to justify) FMC deployment?
  • What are you doing as a consumer with VoFi? Anything?