Welcome welcome welcome to the world of the Internet in Australia.
Even in our largest population center, we can struggle to get 3Mbps downstream on a business-class ADSL2+ connection. Cable penetration is poor in residential areas, and even worse in commercial so unless you're fortunate you can't get cable internet. And because we're such a sparse population spread over such a massive area (4 million people in an area about the size of New York City?) wireless solutions are just as crappy, and expensive because they don't have 18 million potential customers.
I'm in the same situation as you (in case you can't tell), where we have users in a different capital city who have 200ms latency between our terminal servers and their office.
Solutions. Well, they're all mucky I'm afraid:
DFS. You mention you have DFS in your UK branches already. Can these be extended to your Australian office as well? Depending on the size of the folders, it may a good idea to load up a 2Tb drive with a copy of the DFS root, air-mail it to Sydney, get them to copy it onto their local server and then set up the DFS to sync the changes between the two.
Terminal Services. You're sort of screwed here to be honest. High latency does not play well with real-time applications, and apart from changing the laws of physics, if it takes 300ms for the data to get there and back, it will take at least 300ms to register the mouse click, plus about 5 seconds to render whatever context window it opened. BUT, there are things you can do:
- In terms of bandwidth, a terminal server session consumes about 30Kbps. This is less than a dial-up modem. Citrix consumes about 20Kbps and reportedly has better functionality for dealing with high latency.
- Lower the colours to 16-bit
- Disable drive and printer redirection
- Are you having trouble with the server thinking that the clients no longer exist and terminating their sessions? You can increase the number of "failed" contact attempts it takes to drop a session in the registry at
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters] TcpMaxDataRetransmission; it's hex so
0000000a is 10. Default is 3.
- Use QoS heavilly on the remote networks. You don't need someone's
pornYoutube stopping people from actually getting work done
- Citrix has a product that doesn't actually lower the latency, but greatly lowers its noticability. For example, it renders entered text client-side before sending it server-side, so it looks like the text has been entered whilst it's still only half-way to its destination. I forget what it's called
- Printing over terminal services sucks. Even in 2008 R2 with EasyPrint, the XPS files can become massive. Look into something like ThinPrint or Screwdrivers if you're going to be doing a lot of printing from the terminal server.
Choice of internet provider. Australia has two major international link providers. One of them is owned by Telstra, who for many, many years had a total monopoly on the market. They used to be a government-owned company before they were privatised. They still own all the aging, shitty copper lines to the premises, all the exchanges, most of the equipment inside the exchanges and most of the communication between the exchanges. They also held the rest of the country by the balls when it came to international data exchange. Then a few other companies (mainly iiNet and Internode, if I remember correctly) forked out a shitload of money and got their own international link. Try getting a 2nd line from a different ISP and see how it goes. If one line is with Telstra, try iiNet or Internode. If you're already with iiNet/Internet/Optus, try getting a Teltra link (god, I feel dirty just writing that). Steer clear of the low-budget carriers (Dodo, TPG) as they over-sell their services and although 1Tb of quota a month sounds great, when their core routers are overloaded because they're just Cisco 800's (ok, that's an exaggeration) then you're never going to get good quality of service.
Wait. The Australian government is in the process of rolling out a Fibre to the Premesis project called the National Broadband Network. If you're not in one of the planned development areas, then you might be in for a long wait (5+ years). But if the office has not been established (sounds like it has though), then if you can get a convenient location inside the NBN rollout, then that could be worth it (it could be established anywhere from 6 months to 3 years though). 100Mbs fibre terminated at your front door should be a pretty good deal. However, if we have a change of government in the next election (which is highly possible) then you can be assured they will can the NBN and replace it with an LTE wireless network which, whilst reasonable for checking emails on your Blackberry and stalking your ex girlfriend on Facebook, will not be as amazeballs as the NBN.
Apart from all of the above, which are bandaids at best, the other option might be to see if the software they're running can be extended to multiple sites. SQL Merge replication is a common one, but the database and software usually have to be designed to take advantage of it. If you can, then perhaps an always-on merge replication and a local terminal server/application is the way to go.