September 29, 2006
Wireless access for visitors
It was interesting to read Paul’s post on Panlibus regarding wireless internet access in Libraries. My own local library in Bridgnorth has just finished being refurbished and one of the new facilities includes wireless Internet access. This is great, Bridgnorth is just the sort of rural area that can benefit.
Paul goes on to say
I continue to be bemused by the number of commercial organisations that fail (unlike Talis!) to provide some form of network access to visitors. I could name a plethora of big organisations in London and elsewhere that set great store by their meeting facilities and the quality of their biscuits, yet fail to let visitors onto any sort of network for 'security' reasons.
On Thursday morning I experienced this first hand. I attended a Microsoft seminar at their campus in Reading. Once the session had completed I enquired at the reception desk if they had internet access for visitors. Her reply was a predictable "no, sorry", but I must admit their coffee and biscuits were first rate.
Technorati Tags: Libraries, Microsoft, Talis, Wireless
Posted by jimprince at 05:45 PM | Comments (0) | TrackBack
September 07, 2006
Talis RSS Feeds
Over the last week or so there has, among other things, been some discussion about the communication channels used at Talis. One area discussed was how useful RSS is as a medium for delivering content.
I thought it would be useful to provide a list of the Talis feeds that I think Talis customers should be subscribed to.
These are as follows;
General feeds
Talis BlogsTalis PodcastsI've created a short OPML file which you can use to add these feeds into your favorite RSS reader. You can download the file from here. Simply use the import OPML option from your RSS reader of choice.While on the subject of RSS I'd like to recommend a few news readers/aggregators.
If you want to access your feeds via your web browser I'd suggest you try Bloglines. It's fast, free and gets round any restrictive Infrastructure policies.
If you want your RSS to be integrated with MS Outlook I'd recommend NewsGator. Feeds are devlivered straight into your Outlook folders allowing you to track all your emails and feeds in one place. The downside is that it costs $30, but its a small price to pay.
Finally, if you want a standalone application, you can't go far wrong with Snarfer as recommended by Colin Austin on the University of Worcesters ILS Matters Blog. It's a tiny download and is super quick. It's also free, although you'll have to put up with the occasional unobtrusive banner add.
Technorati Tags: RSS, OPML, Talis, Blogs, Forums, TDN, Podcasts, Bloglines, Newsgator, Snarfer
Posted by jimprince at 10:46 PM | Comments (0) | TrackBack
July 09, 2006
Your PC in a wall socket
This has to be the ultimate low power PC. This intriguing device plugs directly into a standard RJ45 wall socket and is the first computer to use Power-over-Ethernet. It consumes as little 5W of electricity yet offers a 500Mhz AMD RISC Processor, 4x USB ports, 128mb RAM, 64mb of flash memory and support for 20bit Stereo and DVI Video. It ideally needs to be connected to a Terminal Server and supports both Citrix ICA and Microsoft RDP.
The obvious advantages are the less desk clutter, improved physical security and low power consumption. Whilst this environment wouldn't suit power users or PC gamers it strikes me as the ideal low cost platform for libraries, schools and Universities.
Posted by jimprince at 12:09 AM | Comments (0) | TrackBack
August 12, 2005
Wireless Authentication
Our initial investigation highlighted the need for distinct security requirements for our staff, customer training equipment and guest users. To not help my hair-loss any further, I ruled out 6 access points. Of course if any students mis-behave they may have to walk the plank in the middle of all the wireless laptops. Further investigation pointed us at VLAN capable access points that allowed separation of traffic on a single access point, using multiple SSIDs along with 802.1x authentication, which is supported by most current hardware and software.
We looked at authentication protocols including WEP and it was not too difficult to decide to use the 802.1x framework for our wireless LANs. With WEP all access points and client radio NICs on a particular wireless LAN must use the same encryption key. In order to use different keys, each access point and radio NIC must manually be configured. This might not be too much of a concern for smaller networks but the task of renewing keys on a network with over 100 clients seemed an administration nightmare. If keys are not updated often then an unauthorised person with a sniffing tool, such as AirSnort or WEPcrack, can monitor the network for less than a day and decode the encrypted messages.
The use of 802.1X offers us an effective framework for authenticating and controlling user traffic to a protected network, as well as dynamically varying encryption keys.
Posted by Saheed Akhtar at 09:37 AM | Comments (0) | TrackBack
July 06, 2005
Why wireless won't kill the Ethernet cable
Reading some of the articles in the computer press you'd think that wireless networking will kill off the Ethernet cable altogether. Indeed our Wireless implementation has been very successful, I'm connected via wireless as I type this, but in no way will it replace our existing Ethernet LAN.
Even with the advances in the 802.11 standard there is still a long way to go. There are a number of technical problems that need to be overcome, limited bandwidth, transmit power and interference to name but a few, not to mention the security implications.
The original Ethernet specification is more than 30 years old and people are still finding new and innovative ways to exploit the technology. Power Over Ethernet (PoE) is a technology that transmits electrical power as well as data over standard CAT 5 LAN cabling and is a good example of this. PoE currently has a limit of around 15 watts but it's more than enough for powering all the VoIP handsets in our offices.
As work continues on increasing the power provided, we could soon see the limit raised enough to power a laptop. The ability to power and recharge your laptop through an Ethernet cable is very appealing. Wouldn't it be nice to ditch that heavy power pack and universal travel adapter?
As far as I'm concerned both technologies have their merits and are both here to stay.
Posted by jimprince at 11:31 AM | Comments (1) | TrackBack
June 23, 2005
Wireless Experience (part II)
As we wondered around the offices with laptops and phone headsets we were picking up very strong signals from all staff including management. So we advise to avoid the same questions and a multitude of confused expressions that you inform users that you maybe carrying out a wireless survey.
On a more serious note a comprehensive site survey helped us define coverage area and data rates and determine the most precise placement of the access points. Our surveying involved both diagramming the coverage area and measuring the strength of the signal. While signal strength can tell you if the signal is strong enough to be received, signal-to-noise ratio (SNR) measurements help compare the signal to the noise. We found that if noise in the band is high enough, it can cause reception problems, even if there is a strong signal from the access point. Because signal strength alone is not sufficient, using both SNR measurements and packet retry count (the number of times packets that had to be retransmitted for successful reception) is the best way to validate the coverage area.
Packet retry count, which should be below 10 percent in all areas, is the ultimate method for determining the edge of RF data reception. You may have areas where the signal is strong, but because of noise floor, or multipath interference, you cannot decode the signal, and the packet retry count will increase. Without an SNR reading, you will not know whether packet retries are increasing because you are out of range, the noise is too high, or the signal is too low.
Posted by Saheed Akhtar at 02:10 PM | Comments (1) | TrackBack
May 24, 2005
Essential Wireless Questions
We began by defining the requirements of our wireless network and some of the following questions were asked.
- How many users require mobility and where?
- What user applications will run over the WLAN?
Listing the applications required by our users helped us determine minimum bandwidth requirements. Often it is over looked that wireless is a shared medium, not a switched medium. Although most applications work over a shared WLAN, it’s not necessarily appropriate for all applications.
Understanding users and their application requirements helps define coverage areas that don’t waste money or compromise security – by sending signals beyond the intended areas.
You can discuss wireless networking in the Infrastructure Forum.
Posted by Saheed Akhtar at 03:38 PM | Comments (0) | TrackBack
May 04, 2005
The Cost Of 3G
For the last year or so I’ve had gprs data card for my laptop, it was on the orange network, kinda worked, but was painfully slow for most tasks, still it got me out a hole once or twice when there were no landlines about.
More recently we’ve been involved with a push to update our mobile technology at Talis, and as part of this we’ve implemented a number of advances in our infrastructure, with Soft phones and VPN’s for home working, Web mail access for mobile users, Instant messaging etc and an ongoing evaluation of more portable kit, lightweight laptops, PDA’s, smart phones, combined with wireless and 3G data connections.
No so long back the old Orange card got replaced with a shiny new Vodafone 3G mobile connect data card, still made by the same manufacturer (Option), but definitely an improvement on the older card.
The drive for getting the cards was mainly to improve the available mobile communications for our roaming staff, but also evaluate the performance of products such as Alto over 3G VPN connections, which could have possible applications for mobile libraries etc.
Funnily enough the Vodafone card seems to have 3G coverage problems at our offices, and drops back to gprs, but back home (about 4 miles outside of Birmingham), I get a 2 bar 3G signal with a 384kb connection, which is fine.
Connection to the office is easy enough, just like any other dial up, add another couple clicks, then you’re on the VPN with access to all the usual resources. After proving everything worked, and zipped along at pretty impressive speed compared to the old Gprs, I thought I’d try a few other things.
The phone exchange at Talis is based on Voice Over Ip (VoIP), and we can make calls via a soft phones on or laptops, Hmmm, I wonder if that will work… (Phone calls with all the economy of having the heating and air conditioning on along with windows open). :-)
On a technical level, it was great to see everything working, Digital voice being transmitted over the 3G network though a VPN tunnel to the exchange off to the outside world, but then you’ve got to look at the costs of such an over engineered conversation…
On a typical low user tariff, it costs about £2 per megabyte for 3G data, and the voice conversation was running at about 400k / minute (with the VPN overhead), so that works out roughly at about 80p min... hmmmmm. Things can work out cheaper if you can find a WiFi hotspot at about £3 for each half hour block, but when you compare this to just using the mobile instead which would cost less than 10p min, and a land line cheaper again, its show how mobile data is still relatively expensive.
Ok, it was a bit of geeky test, and no doubt data on mobile networks will get cheaper over time. However, right now reasonably quick mobile data comes at a premium, and you'll be surprised how quickly you eat those megabytes with modern web content. Certainly the ever increasing number wireless hotspots and mobile networks will drive prices down, and the push to bring such technologies as Instant Messaging and VoIP clients to the mobiles will increase the demand for mobile data, lets just hope the prices start falling sooner rather than later…
Posted by at 08:47 PM | Comments (1) | TrackBack
May 03, 2005
Wireless Experience
We were recently tasked with looking into setting up wireless network access in our offices so that both staff and visitors could access network resources in meetings rooms and breakout areas more easily.
As Ateeq and I are the security guys at Talis and responsible for the security service that Talis offer we were naturally concerned about the security of wireless networks. This made Ateeq wrap up the static WEP based Wireless Access Point (WAP) and take it home – or was it just because he wanted another toy that week?
Talking about toys it wasn’t long before Ateeq added wireless sniffer tools to his PDA and drove into work after reading warnings on woeful wi-fi security on the BBC website. I was quite impressed with the large screen on his PDA but what I found even more impressive was how many pages of wireless access points we picked up on a 10-mile drive. Only half of these seemed to have any security at all, we didn’t try cracking them on this run, which I’m sure if we tried it would not be too difficult dispelling the myth of wireless security. It’s one thing to read about it but it doesn’t really hit home until you experience it.
In our next few blogs we’ll talk about some of the issues we faced including speed, security, standards, compatibility, interoperability, and even signal interference with other devices.
Oh and by the way we are building up the motivation to visit the libraries near us and "learn" about their "secure" wireless implementation.
Posted by Saheed Akhtar at 03:12 PM | Comments (2) | TrackBack
