what is the easiest way to connect two LANs that about 30,40Kms away from

[silvercats]

....from each other other ?

Wireless Boradband(HSDPA) and VPN don't count.
and if we use cables,isn't it be very hard to drag them through cities ,buildings? (if it is about 100Kms part ? take any distance more than about 30.education purpose only)

[JorgeM]

If a VPN connection over the internet is not an option, you may want to contact your local communication providers (AT&T, Comcast, etc..) and find out what type of metro ethernet connections they may have. A provider can simply provide you with an ethernet cable at each end and they handle the traffic through their private cloud.

[rubberman]

A VPN is the usual way, although if your bandwidth needs are great, you might be better off leasing dedicated bandwidth on the fiber optic cables between point A and B. My company (a tier-one mobile phone manufacturer) has data centers in a number of places all over the world. We have that sort of dedicated "pipe" between our various data centers so we can easily shift load from one to another as necessary. Our major data centers are in the US, Great Britain, Singapore, and China, and more regional ones in India, South America, and elsewhere (not sure where they all are). These are multi-gigabit links. So, depending upon the day and time, a phone user in Brazil that wants to browse their Facebook account may be connected to a data center in any of those locations. To the user, there is a small delta in latency, but overall the end-to-end time is very close to the same.

[silvercats]

so you are telling me that we can borrow the cables ISPs have set up already without dragging new cables?
DO normally governemtns allow regualr companies to drag new cables(underground) cables through cities?

[JorgeM]

The service providers such as Comcast, AT&T, Verizon, etc.. will infact lay out new cables when they have done a business analysis in a new area, or for a customer that is asking for services they do not provide in the area. If they see an opportunity to generate revenue, yes, they will deploy new cabling. I have a buddy in that business.

Aside from new cables, these providers already have in many cases, the infrastructure in populated business areas already. If you have two building, as long as the provider is in the area of both buildings, they can usually provide you with a cable at each end, and you dont have to worry about the details. But do keep in mind that this type of service is not as low cost as DSL. Depending on the bandwidth requirements, a small pipe can run several hundreds to several thousands per month.

[silvercats]

oh i see. how do normal Universities and not so bug business connect with other braches in other cities mostly in real world?? VPN or by using ISP cables as mentioned above if the need a bigger bandwidth.?

[JorgeM]

That is correct. For a university with a large campus, they may just run fiber between the building and create their own metropolitan area network. however, for the most part, an ISP provider will have various methods and options to offer their clients. The most inexpensive is for your offices to have internet connectivity and just create VPN tunnels between them. However, the VPN tunnel over the internet is the most risky because you generally do not have a service level agreement on that type of connection over the internet.

You see, the price of a connection is not just about how big the pipe is, but also whether or not the ISP will guarantee the connection. Take DSL as an example. You can get a 10 mb pipe these days with DSL and pay $50 per month, but you call your ISP for a 10 mb metro ethernet connection and they want to charge you $500.00. And you say why? This is beause they will not guarantee the uptime with the DSL connection, but they will with the metro-e connection. On the connection with the SLA (service level agreement), they will credit you money if the connection goes down.

[silvercats]

thanks for the replies ITG-JM and Rubberman.was helpful