Frequently asked questions

What is GPRS?

What does it cost?

How much data do I use?

Where can I roam?

Do you have any setup instructions and drivers?

How do I connect my Laptop to my mobile phone?

What is Bluetooth and how do I use it?

What Data rates can be achieved in the real world?

How do I connect my PALM Vx11?

How do I connect my Compaq IPAQ?

How do I connect my HP Jonarda?

How do I send and receive emails?

What are the arrangements for allocating IP addresses?

Can GPRS provide resilient connections?

Can I use my existing Frame Relay connection with GPRS?

What is the expected latency of a GPRS network? I.e. the round trip message time?

My Infrared (IR.) connection will not work or is unreliable?

Can I use GPRS for video conferencing

Does MMS use GPRS?

Why do web pages look different when using GPRS?

Can I send real-time Audio over GPRS?

How do I share my GPRS connection?

How do I set up a mobile GPRS Internet access point?

Can I advertise on GPRShelp?

 

What is GPRS?

GPRS is a mobile data service offered by the GSM mobile phone networks. It can be used by suitably equipped mobile phones to provide faster WAP browsing without blocking incoming calls.
For business users it can provide mobile access to your emails, your company network and/or the Internet, and is especially good for providing Internet access to your PDA or Laptop PC. Check out our GPRS beginners guide for more information.

 

 

What does it cost?

For WAP access the network providers have tried to price it to cost you the equivalent to standard WAP access - approximately £20 per megabyte. This may sound a lot, but you do get a lot of WAP pages for £20, (1 megabyte gets you between 500-1000 pages) with typical users loading 100-200 pages/month paying £4-£5.

For access with a PC or PDA, this would be prohibitively expensive, so the networks have set up bundles of megabyte of data - all expecting you to know how much data you will use in advance. This will then cost £7-£8 for the first megabyte and then £4-£5 per megabyte after that. The cost comes down for larger users, to £10/month + £1/megabyte per user for 25+ user companies.

How much data do I use?

Connected to a company LAN or fixed access to the Internet you do not usually worry about how much data you are using. When mobile using GPRS there will be both a cost and time factor associated with large data transfers. Clever configuration of your mail system and client, along with optimization of WEB access will both save you money and speed the service. The actual amount of data you use of course depends on how you use it - text only emails are efficient - only taking a few kilobytes of data. Downloading documents or browsing the WEB will quickly increase that. Text only emails, with a correctly configured Email client (e.g. downloading headers to select emails to completely download) may squeeze a complete months use into 1 megabyte.

Home working using a LAPTOP, with a mixture of Email and web access with little regard for data volumes can easily push this up to 40-100 megabytes - very expensive if you are on the wrong tariff.

Downloads on an uncongested network typically run at around 30kbps - this equates to approximately 4.5 - 5 minutes per megabyte.

Configure your Email

 

Where can I roam?

Check with your GPRS network supplier as they usually have far less GPRS roaming partners than they have GSM roaming partners. Roaming is usually totally automatic - you should not need to change any settings while traveling. Oh.. and watch out for GPRS roaming charges which are usually much higher than your local GPRS charges.

	When traveling make sure you connect to the correct network as many countries will allow you to use more than one network for voice but not all will provide GPRS.
	Have a fallback connection setup and tested before you leave - a GSM dial-up networking connection to your ISP will get you out of a fix if GPRS is unavailable.

Your network supplier will need to subscribe to a GPRS roaming network (GRX - GPRS Roaming exchange) - and then you will have access to all other networks who have subscribed to that network.

Once connected your network supplier has a choice of how to connect you to the Internet - the preferred method is to securely route your data back to your own GSM network (Home Network Roaming) where you will benefit from having exactly the same services as you would normally receive in the UK. It is also possible to route your data directly onto the Internet in the country where you are roaming - this may be fine for many but is less predictable (and secure) than the Home Network Roaming.

Do you have any setup instructions and drivers?

We are compiling a collection of useful third party instructions, drivers and utilities to aid your configuration of mobile devices - see Setup help and Drivers.

 

How do I connect my Laptop to my mobile phone?

You have a choice of methods - you can either purchase a GPRS or HSCSD data card to fit in your laptop (this will require its own SIM - try to get an additional SIM on your mobile phone account, and will shorten your battery life) or you can use your mobile phone equipped with GPRS, HSCSD or GSM data.

To use the mobile phone you have a choice of how to connect with the laptop -

	Cable -  Very reliable and is easy to use when traveling
	Infra Red -  Works very well but the phone needs to be carefully positioned making it very awkward to use when traveling. Tip: Use a reflector (e.g. foil sweet wrapper) to bounce the IR. to a more convenient location for you phone.
	Bluetooth -  Sometimes difficult to configure, but once working it is totally transparent, as though you have a (low power) data card in your laptop. The phone may be left in your briefcase or pocket with your computer on your lap on the train. Check out TDK Systems for their add-on Bluetooth cards for PC's, PALM and PocketPC devices.

Setup help and Drivers

What Data rates can be achieved in the real world?

The maximum speed will be determined by capabilities of your GPRS radio (often 14kbps up and 42kbps down - see the technical section for a fuller explanation) these figures will never be achieved in the real world.

Other factors include:

·         The handset capability (the number of time slots it supports)

·         The number of users of both voice and GPRS in your vicinity

·         Congestion on the network or system providing the data

·         Congestion on the Internet

·         Congestion on your company LAN

·         Congestion on your company LAN connection

 

Read the theory

 

How do I connect my PALM Vx11?

An IR. (Infra Red) connection between the PALM and mobile phone is used to synchronize the calendar, tasks and provide Email access. To browse the web or WAP a PALM browser application will be required - these can be downloaded from the PALM web site. TDK Systems produce a Bluetooth module which fits on the expansion connector, or you may upgrade to a new PALM with a SD memory card slot and PALM SD Bluetooth modem.

Setup help and Drivers

 

How do I connect my Compaq IPAQ?

If you have an older IPAQ you may connect to the GPRS network using an IR. link to your mobile phone or a expansion jacket equipped with a Bluetooth card (TDK Systems Bluetooth jacket also provides an additional Compact Flash card slot for further memory expansion.) or a GPRS data card (nor recommended because of the additional power consumption). The best choice for a new purchase is a model with built-in Bluetooth.

Setup help and Drivers

 

How do I connect my HP Jonarda?

The HP Jonarda 565 has a Compact Flash expansion socket, which is compatible with the 'Socket' Bluetooth card.

Setup help and Drivers

 

How do I send and receive emails?

As long as you use Web (Internet) based Email (using POP servers) you can easily configure you mobile device to retrieve emails as if you were directly connected to the Internet. If your Email server is located on a company LAN behind a firewall then you need to either redirect emails to a Web based Email service or your company needs to provide WAP or Secure Internet access to your mail account.

 

What are the arrangements for allocating IP addresses? 

IP Addresses are usually allocated dynamically by your GPRS network (as with a traditional dial-up ISP connection). Some large business customers can have static IP addresses for their group of users.

 

Can GPRS provide resilient connections?

It is possible to negotiate with your GPRS network supplier to have multiple leased lines or Frame relay connections to their GPRS network.

 

 Can I use my existing Frame Relay connection with GPRS?

Yes  - at least two of the GPRS network suppliers in the UK have frame connections with BT's Frame relay service. PVCs (Private Virtual Circuits) can then be set up between your network and the GPRS network.

 

What is the expected latency of a GPRS network?  I.e. the round trip message time?

Round trip times are typically in the order of 800 - 1000 ms.

 

My Infrared (IR.) connection will not work or is unreliable?

It has been found that the IR. port on some laptop computers is overloaded if the phone is placed too close. If IR. refuses to work or is unreliable try moving the phone 20-30cm (or more) away from the laptop.

 

Can I use GPRS for video conferencing?

NO not with current GPRS devices.

The data rates currently available on GPRS are not high enough to work with standard video conferencing programs. It may be possible to set up a one-way conference but the user experience is terrible. Also - most GPRS devices have a much lower uplink speed than the downlink, you might get only 10kbps uplink (from the mobile) and 30kbps downlink (to the mobile). 30kbps is fast enough for a very small, slow refresh video - but it cannot be used to connect to another GPRS device because then both call directions would be limited by the 10kbps uplinks.

If you set up a one-way video link - to the GPRS mobile, set the video size as small as possible and keep an eye on the data transfer because if you are on the wrong tariff it could be expensive. At 30kbps (a typical max uncongested downlink speed) you will get 4.5-5 minutes per megabyte.

 

Does MMS use GPRS?

The new mult-media-messaging services being launched by many GSM operators use GPRS to transmit the messages between users. The service does not use the standard GPRS billing and you will not need a GPRS subscription to use it (but you will need a compatible phone). The service is charged per MMS to you phone bill. If you transmit the equivalent message over GPRS (not using the MMS service e.g. messaging or Email) it will usually be much cheaper.

 

Why do web pages look different when using GPRS?

To make web pages download faster when using the relatively slow GPRS service, many network operators have implemented 'Optimization servers' on the network. These do many things to a web page to make it appear on your screen quicker including:

• Reordering of text/graphics so that you can read the content while the pictures are still downloading.
• Removal of unnecessary tags etc. Many pages have a lot of unnecessary HTML which is not displayed.
• Recompression of graphics to make them smaller - a slight reduction in quality is often not noticed.

Unfortunately the side-effect of these will be that some pages will look slightly different (but they do appear much quicker). If you want to load a page "uncompressed" try holding down "Ctrl" while selecting the "Refresh" button.

 

Can I send real-time Audio over GPRS?

A GPRS connection will allow you to transmit audio at a much higher data rate and hence quality than a standard GSM phone call. But, because the bandwidth is a shared resource, you will not be guaranteed sufficient data rates when you need them for real time conversations. Also GPRS has high latency - the time taken for data to pass through the GPRS network to the Internet is approximately 1/2 second - round trip 1 second - this will make conversations difficult.

If you try this (and can afford the bill as it will use lots of data) ensure you have a GPRS device with sufficient uplink slots - many phones are designed for a fast downlink and only provide a low bandwidth uplink. Some of the new GPRS data cards for laptops provide a much better four slots in both directions providing a theoretical maximum of 56kbps.

 

How do I share my GPRS connection?

If you use a Microsoft Windows computer to access the Internet using GPRS, the connection may be shared using ICS (Internet Connection Sharing) which is included in Windows. If the computer is equipped with Bluetooth then all your Bluetooth equipped PDAs can share the Internet connection while within range and use GPRS when out of range. The Internet connection may be provided by a single GPRS data card or phone, and then shared amongst multiple devices.

 

How do I set up a mobile GPRS Internet access point?

First select a high performance GPRS card (such as the Sierra Wireless AirCard 750). Install the card and setup a GPRS connection to test.

Disconnect from GPRS and then turn on ICS (on W2000 this may be found at Start/Settings/Network and dial-up connections - right click to get the properties window and then turn on in the "Sharing" tab).

If using Bluetooth, you will need to 'Pair' with each of the devices to be allowed access, and the PDAs need to be set to "Connect to Network Access" in their Bluetooth manager.

The result is that all the devices will have concurrent access to the GPRS Internet connection and will be able to send and receive Email as if they had their own connection.

 

Can I advertise on GPRShelp?

GPRShelp has a growing international readership, and is being accessed from most countries in Europe in addition to the USA. If you are interested in advertising to our mainly business focussed readers please contact GPRS Advertising with your requirements.