Enhanced Bit Repair IP Fast Reroute Mechanism for Rapid Network Recovery

Round 1

Reviewer 1 Report

This paper proposed a protocol called Enhanced Bit Repair (EB-REP) for Fast ReRoute (FRR) in link/node failures in protected IP networks. The developed protocol works proactively by calculating alternative paths if there are single or multiple nodes/routers or link failures in a network. Besides, it provides a fast reroute for all the flows associated with a router. These are significant enhancements from authors on their existing work Bit Repair (B-REP), which provides reroute for a single flow in case of a single link or node failure.

I would suggest the following modification to improve the quality and readability of the paper.

1. In the abstract, it appears that it is an entirely new protocol. However, it provides significant improvements in their existing work B-REP. The abstract could be modified to describe their existing protocol and its drawback and how their new protocol address those problems. 
2. It appears that in line 252, there is a typo as 0B-REP is written in place of B-REP
3. In Section 3, a detailed description of the earlier protocol B-REP's inner workings is provided, but shortcomings are provided only in a single sentence. It would be better to provide more details of the B-REP shortcomings, making the description a better segue to Section B, where EB-REP is described.
4. In line 465, gendered language has been used for the router. It could be written "it" instead of "he".

 

 

Author Response

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Author Response File: Author Response.docx

Reviewer 2 Report

The manuscript deals with a very interesting subject, related to a new IP FRR mechanism called Enhanced Bit Repair (EB-REP), which offers rapid failure protection for IP-based infrastructures.

The originality of the paper as well as its results are satisfactory and sufficient for publication in the journal.

However, prior to publication, the following issues must be addressed:

1) the authors are correctly refer to several recent works/references targeting the proper calculation of alternative paths. However, the authors do not take into consideration, or at least explicitly mention in the references, the publications related to routing algebra that must be taken into consideration when combining several routing metrics. So, the authors are encouraged to add the following references and, of course, check the routing metrics they are using in their analysis ans whether these are accepted under the routing algebra formalism.

• J. L. Sobrinho, “Algebra and algorithms for QoS path computation and hop-by-hop routing in the Internet,” IEEE/ACM Trans. Netw., vol. 10, no. 4, pp. 541–550, Aug. 2002.
• J. Sobrinho, “Network routing with path vector protocols: theory and applications”, in ACM SIGCOMM, 2003, pp. 49-60.
• M. G. Gouda, M. Schneider, “Maximizable routing metrics”, IEEE/ACM Transactions on Networking, vol. 11, no. 4, Aug. 2003, pp. 663-675

2) In the introduction, and in particular in the sentence: "The network is therefore required to meet very specific and diverse qualitative and quantitative parameters for a diverse range of services operated, where others are for real-time communication services [3], other for wireless sensor services [4]–[8]", the authors must also add the following interesting reference, that provides WSN simulator based on the routing algebra and IETF documents: P. Karkazis, P. Trakadas, T. Zahariadis, A. Hatziefremidis, H. C. Leligou “RPL Modeling in J-Sim Platform”, in 9th International Conference on Networked Sensing Systems, June 11-14, 2012.

3) In the conclusions section, the authors must better describe and highlight future work, towards, for example, larger networks or under specific attacks.

Author Response

Please see attachment

Author Response File: Author Response.docx