Advantages of MPLS

A interview always start with the question called "Advantages of MPLS" and most of the time students don't know much about it and start fumbling with not good answers. I am giving few quick answers about MPLS advantages, if some is having other than that please share.

1. No propagation of routes in the core of service provider.
2. In legacy GRE customer is responsible for the management but in case of MPLS SP is responsible.
3. Customers can use the same ip address which is not possible in case of GRE.
4. MPLS saves cost as compared to ATM or frame relay network.
5. MPLS increase the response time.
6. Customers can have the QOS according to their requirements.
7. Fast reroute features by using traffic engineering.
8. MVPN support which saves lot of bandwidth.

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SeaMeWe-4 Undersea cable cut

Another undersea cable cut made Middle East limited access to internet. The main SeaMeWe-4 cable suffered a "shunt fault" and came into contact with sea water somewhere in the Mediterranean.
Fortunately, this dependence on SeaMeWe-4 will come to an end this year. The consultancy says that "five new cables are scheduled to enter service between Europe and Egypt in 2010. The first two, Telecom Egypt’s TE North cable and the IMEWE consortium cable, will enter service in May. Orascom’s MENA cable, the Europe India Gateway consortium cable, and Reliance’s FLAG Hawk cable are all expected to follow before year-end 2010." Capacity will skyrocket, and the new cable will also bring helpful redundancy to the region.
Source:- Arctechnica

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Multicast Interview Questions For Service Provides Candidates

Multicast Interview Questions For Service Provides Candidates

1. Why multicast is required in MPLS SP cloud?
2. Does MPLS understand multicast?
3. What is Assert message in multicast and when these are required?
4. What is the difference between dense mode, sparse mode and sparse dense mode?
5. Can we use dense mode by using sparse mode? If yes, then what is the use of sparse dense mode?
6. What is the difference between (*,G) and (S,G) entry?

7. In sparse dense mode if we don’t use RP what will be the effect?
8. In SSM( Source Specific Multicast) how to advertise RP?
9. Which type of entries created in Auto RP, BSR, MSDP and SSM mode?
10. What is the difference between ip igmp join group and ip igmp static join group?
11. SSM requires IGMPv3 but in MPLS SP cloud why we don’t use IGMPv3?
12. What is the advantage of using SSM in MPLS SP cloud?
13. How to maintain S,G entry for a long time?
14. How to select Multicast Group? Is there any type of overlapping happens, if yes then what’s its advantage and disadvantage?
15. In MPLS cloud, if we define two loopbacks in multicast for creating hierarchical cloud, what will happen?
16. I am receiving RPF failure message at PE end and don’t have access of CE router, how to solve the problem without having CE access?
17. Difference between Shortest path tree and shared path tree?
18. Difference between data and default mdt?
19. Does default mdt works without data mdt and vice versa?
20. Can MPLS SP cloud have SSM and MSDP at same time? If yes, then what’s the reason for specifying two protocols?
21. What is difference between address-family ipv4, vpnv4 and mdt?
22. If SP cloud doesn’t use address-family mdt what will happen?
23. If you ask to design a MPLS based multicast network, what will you suggest?
24. What is MDT tunnel?
25. Can we modify MDT tunnel?
26. What is the multicast source address and group address in MPLS SP cloud?


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