I know few about network knowledge, I think this a router or firewall function:
There are three countries, Europe is 10.1.x.x, Singapore is 10.2.x.x, Korea is 10.3.x.x, All of them can access each other.
Now we have published one European web server 10.1.1.1 in Europe, can we publish the web server 10.1.1.1 on Singapore and Korea firewall again?
let me make it clear for you.
1. User request DNS server to resolve your address . Ex: cisco.com
2. Your DNS server replies with possible options ( Addresses of your web servers in different countries ) : Ex: 184.108.40.206 for Europe - 220.127.116.11 Singapore - 18.104.22.168 Korea . Round Robbin algorithm change the priority of request each time .
So you can solve your problem using DNS configuration as simple as possible
On the other hand, public IP addresses are route-able with some considerations! you can not set a public address where ever you want .
What are 10.1.1.1 and 10.2.1.1. and 10.3.1.1 in your example? Public or private ?
I suggest you to draw a network diagram here to make everything clear . Then we will understand your scenario perfectly .
If it's just a web server, never mind! Web servers are located all around the world and people send their request to visit web sites without any problem.
But, sometimes service architectures think to an approach to optimum response time. One the most popular ways is yours ( Multiple web servers in different locations ).
Now, Could you tel me how your clients visit your web server? Using URL or IP ?
If the answer is URL, you should work on DNS side and some solutions like Net Mask Ordering end etc . If the answer is IP, it's really simple to implement . Users in each country must browse IP address of the web server which is located in his country .
OR, you can implement the scenario using sub domains . Ask the client to choose his country ,then redirect him to appropriate sub domain. For Ex :
en.test.com - > 10.1.1.1 ( which is located in US)
ch.test.com -> 10.2.1.1.( which is located in China)
sg.test.com ->10.30.1.1 ( which is located in Singapore)
This is a network engineer view, a service engineer can solve it in upper layer however .
Not using the same public IP addresses or private IP if this is a lab exercise.
It seems you are concerned about latency based on the location?
Approach might be different depending on the content severed by the web server(Dynamic or Static) and also depending on whether its a private service or publicly available content.
In general for static content you could distribute multiple copies of your website which are synced together at different physical locations and load balance them based on DNS or based on the Country or IP address scheme.They'd have different IP addresses but the clients would find the service through the domain name.
Nowadays most popular approach is through CDN where you'd cache your content at different entry points of networks.
Services with dynamic content would have approaches unique to the content,as an example if its a shopping cart you'd have multi store shopping carts
Hope that helps..
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