Wireless Mesh Network

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802.11s wireless mesh networks consist of access points, stations and ..... layer 3 and generated a custom kernel for the Samsung Galaxy. S III[8]. 5) Arduino.
International Journal of Computer Science and Information Security (IJCSIS), Vol. 14, No. 12, December 2016

Wireless Mesh Network IEEE802.11s Computer Science department University of Gujrat Sialkot Campus Sialkot,Pakistan [email protected]

Farooq Ahmed Computer Science department University of Gujrat Sialkot Campus Sialkot,Pakistan [email protected]

Atizaz Ali Computer Science department University of Gujrat Sialkot Campus Sialkot,Pakistan [email protected]

Zain ul Abedin Butt Electrical Engineering department CASE University Islamabad,Pakistan [email protected]

Muzamil Mehboob Information Technology department University of Gujrat Sialkot Campus Sialkot,Pakistan [email protected]

Asif Hussain Khan Information Technology department University of Gujrat Sialkot Campus Sialkot,Pakistan [email protected]

Ahmed Waqas Electronic System Engineering department Quaid e Awam UET Nawabshah,Pakistan

Jabar Mehmood Computer Science department University of Gujrat Sialkot Campus Sialkot,Pakistan [email protected]

Nadeem Sarwar Abstract— The urge to go mobile has been one of direst desires of mankind since decades. Back in 1997, scientists and the engineers of IEEE introduced a standard which is being used now all over the world under the unlicensed bands 2.4 and 5 GHz. The emerging demand of WLAN (Wireless local Area Network) in offices, corporate and the industrial sector and city wide university campuses forces the Task Group S of IEEE to come up with further enhancements in the family of 802.11 standards. Since 2004, 802.11s has introduced new enhancements related to wireless frame forwarding packets, security and routing capabilities at data link layer. This article describes the mechanism, architecture and its latest amendments in the family of IEEE 802.11 wireless mesh network which is named as 802.11s.The paper also covers the benefits of using the 802.11s standard, a comparison with any other existing standard competing with it in the market and the names of those companies who are producing devices which are capable of supporting the 802.11s standard. We will discuss its viability to implement it on open source platforms (i.e. openwrt).

I.

INTRODUCTION (HEADING 1)

It took seven years of struggle and hard work for IEEE to introduce amendments and new features to 802.11 standards, which they named 802.11s for mesh networking. The Task Group S of IEEE officially published this amendment in 2011.They prioritized their work on meshed networks, in which they offer innovative features that were embedded into the 802.11 standard. It solved many issues. i.e. WPA/WPA2 pre-shared key authentication attacks and the collision of data packets between its neighboring AP’s in condense wireless mesh network topologies. WLAN technology is an ever growing technology mainly in QOS (Quality of Service) and high speed wireless techniques (600 Mbits/s). WLAN mesh networks feature a higher data transmission rate due to shortened communication distance, expanded network capacity through spatial frequency reuse, automatic network configuration and improved robustness due to a route recovery mechanism [1].

Keywords-component; mesh network; protocol; openwrt; wi-fi

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International Journal of Computer Science and Information Security (IJCSIS), Vol. 14, No. 12, December 2016

A. Why need Amandement Due to fierce demand for mobile wireless networks, the need has emerged to go wireless everywhere, even where connecting an AP with a switch is not possible due to environmental constraints. As we know, Ethernet cable provides working connectivity up to 100 meters, only which puts constraints in the positioning of access points in the middle of large indoor halls, warehouses; and this issue is even worse when we provide wireless connectivity to outdoor environments (e.g. outdoor industrial areas, parking lots and plazas, and covering some outdoor sports activities). But with new amendments in 802.11s we can almost cover whole cities, vehicle tracking and wireless security camera monitoring without any delay and disconnection. The benefits and usage of the 802.11s standard is limitless and ever growing by leaps and bounds.

Figure 1: Mesh Network Architecture [1]

A. Explaination

B. Overview of 802.11s Standard The IEEE 802.11s task group was formed in May 2004 to standardize the technologies that would be needed to deploy WLAN mesh networks. This work involved the creation of usage models and requirements necessary for selection proposed technologies and the preparation of formal procedures for making selections. A call for proposal (CFP) was issued in January, 2005. By the time of meeting 1st March 2006, 2 candidates out of 15 submissions had survived and these were eventually combined into a single draft version of a standard specification [2][3] based on the DoCoMo proposal. The plan from here on is to refine the specification into a form that will win final approval. These standard activities were expected to be complete by June, 2008 [1]. And then in June, 2011, the fifth recirculation Sponsor Ballot, on TGs Draft 12.0, was closed. The draft met with 97.2% approval rate and it was officially accepted to be implemented on Wifi devices. II.

The above figure depicts all the different components of the mesh network topology. But the components are not all mesh capable devices. In the figure above, the end stations 'H' and 'I' are simple 802.11 clients associated with a device which has the functionality of AP. Node J, for example, have both functionalities of Mesh AP and Mesh point in the same device. When it links with other members in the mesh, it becomes the MP’s in the mesh. Similarly, nodes of S, M and P have the functionality of mesh points and AP co-located which bridge 802.11 data frames received from customers in DS wireless links in the MBSS upstream. The nodes M, P represent the functionality of Wireless Portal, which provides the conversion of wireless frames to wired interfaces. The node J represents pure functionality of Mesh Gate and performs the conversion of frame from 802.11s to 802.11. By considering the mesh station in the MBSS, a next hop mesh station on the path to the destination mesh station is called a precursor mesh station where E is a precursor mesh station for J or D and their next hop on the path to mesh STA F.

WIRELESS MESH NETWORK(802.11S) ARCHITECTURE

802.11s wireless mesh networks consist of access points, stations and gateways. The diagram given below exhibits the architectural overview of network elements which are used and its role in the whole network topology.

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AP: Wireless Access Point. In the above diagram the nodes J, M, P & S represent access points.



Mesh STA: Wireless Station is that which implements the mesh facility. In the diagram all nodes except H, I, K, L, N, O, Q and R are 802.11 clients or Non-AP STAs.



Mesh Gate: Any entity that has mesh station (STA) functionality and provides access to one or more distribution systems, via the wireless medium (WM) for the mesh basic service set (MBSS). (Nodes F, J, M)



Mesh BSS (MBSS): A basic service set (BSS) that forms a self-contained network of mesh stations (STAs). An MBSS contains zero or more mesh gates. (All nodes having the mesh point or mesh STA functionality run a MBSS).



Portal: The logical point at which the integration service is provided. This is the node that bridges between 802.11 and non 802.11 networks. In the

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International Journal of Computer Science and Information Security (IJCSIS), Vol. 14, No. 12, December 2016

above diagram, Nodes F, M and P are portals bridging the wireless (802.11) and wired networks. •

MCF (Mesh coordination function): A coordination function that combines aspects of the contention-based and scheduled access methods. The MCF includes the functionality provided by both enhanced distributed channel access (EDCA) and MCF controlled channel access (MCCA).



MCCA (MCF controlled channel access): A coordination function for the mesh basic service set (MBSS).



Precursor: A neighbor peer mesh STA on the mesh path to the destination mesh STA that identifies the mesh STA as the next-hop mesh STA.



Source: A mesh STA from which a MAC service data unit (MSDU) enters the mesh basic service set (MBSS). A source mesh STA may be a mesh STA that is the source of an MSDU or a proxy mesh gate that receives an MSDU from a STA outside of the MBSS and forwards the MSDU to a mesh path. III.

And last but not the least its self-recoverable feature that makes it a favorable future upcoming technology. With this feature, if one wireless access AP went down the other redundant AP within its surrounding suddenly detects the failure and again organizes the election process on the base of its embedded protocol. The one with high ID get the priority and replaces the position of that AP within no time. This benefits the wireless engineer without going to the site and updating the wireless network remotely through some wireless distribution software. 9

Connecting a wireless mesh AP in a network would be a security concern; because two mesh AP’s can easily peer with each other by exchanging messages with each other. So connecting a rogue AP by some fake user would be a security threat in a network. But in 802.11s mesh networks there are AMPE (Authenticated Mesh Peering Exchange) messages or simultaneous authentication which prevents the rogue user from connecting within the network without authentication. There are some other technological features which are described below.

TECHNOLOGY FEATURES

Smart Wi-Fi technology – Wireless Mesh is the latest and most advanced technology that is combining the features of the 802.11 predecessor family that prevents the shortcomings of the two technologies cloud mesh, Wi-Fi and mesh Wi-Fi. This technology has included many smart features in transmitting and routing data. Hybrid Wicell fully satisfies all the needs for wireless solutions, operates intelligently and contains many exceptional features which don’t exist in other technologies. 9

Backhaul

The possibility of connecting several AP’s and providing multiple redundant connection in which the multiple inter-link mesh AP’s topology is formed is called Back-hauled which forms a mesh cloud connected with main distribution points and wired networks. 9



Wi-Fi name (SSID) and one channel for the whole system



Plug and play and self-configuration of the two systems: Gateway which connects to LAN cables and relay which does not connect to the LAN/Internet cable when supplied with electricity.



Smart routing the best gateway among many other gateways.



Automatically connect to other gateways.



Seamless roaming beyond traditional WLAN boundaries allows users to move their devices such as laptops, smart phones freely from one place to another.



Limits the number of the users accessing to a Hybrid Wi-Fi mesh station. Each station manages its own bandwidth.



Automatically and unlimitedly connects Hybrid Wi-Fi mesh stations to each other to create a complete mesh Wi-Fi system.



The whole Hybrid Wicell system uses IP LAN.



Most stable and strongest signal coverage in the market with MIMO standard. Data transmission speed reaches 300xMbps. The technology applies to any scale of project and supports all IP based services.



Hybrid Wi-Fi network controller. Free software which controls all activities of hybrid Wicell stations.

Flexibility

One of the major features of wireless mesh networks is its increased wireless flexibility with wired networks. As all access points are connected with each other by multiple paths due to which it provides greater flexibility and the chances of disconnection from the network is minimal. So to speak wireless network availability would be almost 100 percent. It not only provides the wireless availability but also selects the best possible redundant path in case of failure. 9

Security

Self-Evolving

One of the explicit features of a wireless mesh network is self-evolving. In all mesh access points there is an algorithm embedded that detects the best path to be taken for wired and wireless networks. 9

Self-Recovery

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International Journal of Computer Science and Information Security (IJCSIS), Vol. 14, No. 12, December 2016

IV.

9

FEATURES COMPARISON WITH OTHER WI-FI TECHNOLOGIES

We have compared some technological features of wireless mesh networks with other wi-fi technologies, the results are describe in the table below. TABLE I.

Scalability: Single mesh networks are generally not scalable because system capacity is reduced as more mesh APs are added. Dual- or multi-radio mesh where access and backhaul radios operate on different frequencies, increase scalability.

COMPARISON OF WIRELESS TECHNOLOGIES Mesh

Hybrid Wi-Fi

V.

Technology Features

Traditional Wi-Fi

Mesh Wi-fi

Cloud Wi-Fi

Automatic Expansion

No

No

Yes, automatic and unlimited

Yes, Automatic and unlimited

Smart routing

No

No

Yes, but slow

Yes, Very fast

Gateway Controller

No

Yes, the cost is very high. If malfunctions occur with the gateway controller, the system will fail.

Yes, the basic features are free, If malfunctions occur with the gateway controller the system will fail.

Yes, the completely free, If malfunctions occur with the gateway controller, the system will still works.

No

Yes

No

Yes, via real time

Deployment for all scales and requirements

No

No

Yes

Yes

Application

Limited internet LAN

and

Limited internet LAN

Internet and

Wireless mesh network nodes broadcast with each other to create paths with other non-neighboring nodes. It is the responsibility of the routing protocols to maintain, create and search a path. Routing protocols for wireless mesh networks are mostly designed for mobile ad hoc networks, but there are some issues between wireless mesh networks and mobile ad hoc networks which are described in the following table.

Mesh

Full Roaming

MESH PROTOCOL

TABLE II.

Internet LAN , IP Camera , IP TV , VOD

A. Benefits of Wireless Mesh Network 802.11s benefits are described below. 9 Ease of planning and deployment: Intelligent nodes mean less site surveying; indoor and outdoor nodes can coexist. 9 Reduced backhaul requirements: Several nodes are able to use one wireless/wire line dedicated point-topoint or point-to-multipoint link. 9 Resilience: Data packets have multiple paths and can be dynamically rerouted around failed nodes or interferences transparent to the user. 9 Expandability: New nodes can easily be added to self-adjusting networks.

ISSUES BETWEEN AD-HOC NETWORK AND MESH NETWORK

Issues

Wireless Ad Hoc Network

Wireless mesh network

Network Topology

Highly dynamic

Mobility of nodes

Medium-High

Relatively static relay nodes fixed Low

Energy constrain

High

Low

Infrastructure constrain

Infrastructure less

Partially or infrastructure

Routing

By mobile nodes

By fixed nodes

Routing performance

On demand preferred

Deployment

Easy to deploy

routing

fully

fixed

Fully/partially distributed hierarchical /table driven routing preferred Some planning required

Protocols are always defined and modified when users are not satisfied in their wireless domain. Depending on the need of the user, protocols define what information and message format should be selected for the calculation of routing metrics in a wireless environment. In wireless mesh networks nodes always communicate with its neighboring nodes by sharing its topological and routing information. On the basis of discovering, establishing and maintaining routes in WMNs and mobile ad hoc networks, protocols are classified into three categories:

B. Issues with wireless Mesh Network There are some critical unsolved issues in wireless mesh networking which are described below 9 Latency: The more nodes there are in the network, the more hops to route traffic, meaning increased latency. 9 Security: Point-to-point communications are more predictable. Routing from multiple different nodes means greater vulnerability and exposure to unauthorized access if adequate controls are not established. Rogue access points can be easily set up within the mesh. 9 Non-incremental network deployment: Meshes don’t lend themselves to incremental approaches; they have to be almost completely built out within a coverage area to be useful.

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Proactive Protocols



Reactive Protocols



Hybrid Protocols

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A. Proactive protocols

C.

Proactive routing protocols periodically update its routing information and share the whole topology with other nodes in a network due to which at any instant each node knows its reach ability for other nodes. This technique reduces the time of the route discovering message between different nodes which results in less consumption of network bandwidth. Proactive protocols give best results if they are used in a small environment because then it’s easy for each node to maintain and look up small routing tables. A list of some proactive routing protocols are Destination Sequenced Distance Vector (DSDV), Optimized Link State Routing (OLSR), Topology dissemination Based on Reverse-Path Forwarding (TBRPF), Open Shortest Path First – MANET (OSPF-MANET), Fish-eye State Routing (FSR) are some of the proactive routing protocols[12].

Hybird protocol Hybrid protocols are the combined design of both proactive and reactive protocols. But hybrid protocols mostly use proactive protocols, because these protocols keep the path to the node in the area of the source. But for nodes these protocols behave like reactive protocols after that area. So, the challenge is to know the point at which they change from proactive to reactive protocols.

D. Routing Protocols There are some routing protocols of wireless mesh networks which are famous, and research groups are still trying hard to put the best characteristics of all the given below protocols in one protocol. But there vision to become reality takes time.

B. Reactive protocol Reactive routing protocol routing tables are constructed on the requirements of nodes, and the complete topology of the network is not shared with other nodes in a network. They have to send a request by flooding the network to know the path of the other node. This incurs routing delay in receiving packets to other nodes due to high broadcast of discovery messages to the nodes. But at the same time it reduces the overhead of traffic control messages in a network. Reactive protocols get priority over proactive protocols, where there is a need for continuous mobility. Dynamic Source Routing (DSR), Ad-hoc On-Demand Vector (AODV) and some other extensions derived from AODV are reactive routing protocols[12].



OLSR



BATMAN and BATMAN-Advanced



HWMP



Babel

E. OLSR is the oldest mesh routing protocol. It is defined by the Internet Engineering Task F. Force (IETF) Request for Comment (RFC) 3626, and was the leading candidate of routing G. Protocol for IEEE 802.11s [5].But its new version is more stable and sharp than compared to older ones. OLSR is a proactive layer3 protocol that gives portability to other systems and enables the protocol to span link layers. 1) OLSR OLSR is a proactive protocol that uses a link-state algorithm to decide on which path would be the optimized between different nodes. In OLSR, to increase the data throughput concept called dynamic Multi-Point Relays are introduced that makes the optimized routing map in a network. This is achieved by selecting only a subset of neighboring nodes to relay data instead of every node acting as a relay[13].This concept not only reduced the broadcast packets when some new nodes comes in or goes down but also reduces the number of packets that are required to develop a new routing map. 2) BATMAN and Advance BATMAN BATMAN (Better Approach To Mobile Ad Hoc Networks) is another proactive protocol layer 3 for establishing multi-hop routes in mobile Ad Hoc network which is routing on ip address and advance BATMAN is a proactive layer 2, which is self-assembling in a MAC address. BATMAN is more efficient and scalable because of the distributed knowledge of network topology .BATMAN-Advanced promotes its development and provides support because of an active open source community. The B.A.T.M.A.N protocol is a much

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International Journal of Computer Science and Information Security (IJCSIS), Vol. 14, No. 12, December 2016

more feasible protocol in uncertain wireless environments due to its periodically broadcasting originators messages to its neighboring nodes about its existence. And it uses simple algorithms which makes it a better protocol as compared to those which are based on link state algorithms. 3) Hybrid Wireless Mesh Protocol (HWMP)

consistent interfaces to make their projects more manageable. We therefore spent a little time examining the ad-hoc features of DD-WRT, but this provides minimal support for mesh routing protocols. 2) OPEN WRT Open WRT is a Linux based firmware program for embedded devices such as residential gateways. It is a very versatile firmware development environment for developers and a firmware for advanced Linux users that establish the DDWRT and many other router firmware packages. The most important routers seem to be the Linksys WRT54G series and the Asus WL500G. Although the user interface is relatively undeveloped, command line control, allows the protocol packages to be installed and configured. 3) Microsoft Windows

One of the most promising features of Hybrid Wireless Mesh Protocol (HWMP) is that routing table builds and remains in Data link layers which let the upper layers assume that all devices are one hop away. HWMP is the default routing protocol in the draft IEEE 802.11s standard [5]. According to a current draft (D4.0), it gives the flexibility of on-demand (reactive) path selections with proactive topology tree extensions [13]. Hybrid Wireless Mesh Protocol (HWMP) is an open source implementation open802.11s that provides a relatively weak supporting community for development and use. Today it is compiled into most versions of the Linux kernel. It is the standard in IEEE 802.11-2012. But unfortunately, we did not find a satisfactory performance comparison of HWMP over competitors for 802.11s. According to the research of some engineers “to prevents outside attacks Secure HWMP (SHWMP) and Privacy Aware SHWMP (PA-SHWMP) propose a method for nodes to authenticate each other”, but still there is no implementation but engineers are trying to accomplish practical implementation of those protocols[5]. 4) Babel Babel is one of the newest mesh routing protocols. It is defined by an experimental IETF RFC 6126[6].It has been shown assembled and improved. This protocol is twice as fast as BATMAN and controls more traffic through its efficient path selection method. Babel uses many of the same route cost metrics as HWMP, but does not require a specific routing strategy. It is considered a proactive protocol bus that has also reactive features. Its implementation is available in Linux, Open wrt.

Microsoft explored mesh networking early on, creating and evaluating a “Mesh Connectivity Layer” (MCL) in 2004[7]. This software utilized a refined version of DSR, which considered link quality during calling paths. More paramount thing is that, it packaged the protocol as a network driver, which manifests to utilize as a virtual network adapter while transparently utilizing one or several physical adapters. 4) Android Android and Apple OS platforms are of continuing interest because of their dense, power--efficient integration of sensors, processing, and communications. But Google itself shows no interest in mesh networking on android operating systems. But many other communities are working on that platform. The BatDROID app supplies a layer 3 protocol. Recently Smart Phone Ad-Hoc Networks (SPAN) implemented OLSR-D on layer 3 and generated a custom kernel for the Samsung Galaxy S III[8]. 5) Arduino Some initial tasks were performed onto the Yun Platform to port the Open WRT platform that enabling the Yun to participate in a mesh network [9]. 6) Raspberry Pi

H. Firmware Platforms Mesh protocols can be implemented on the following firmware. • DD-WRT • Open WRT • Microsoft Windows • Android • Arduino • Raspberry Pi • Mesh Packages 1) DD-WRT

Air mesh combines the BATMAN-Advance layer 2 mesh protocol into Raspbian[10]. OpenWRT has been ported to the Raspberry Pi platform19 that enables it to serve as a mesh router. Layer 3 protocols, such as Babel, have been running directly on the Raspberry Pi[11]. 7) Mesh Packages Enthusiast communities have produced many packages to serve the needs of the community of mesh networks. Quick Mesh Project, Air Mesh, Byzantium, Project Mesh net, Commotion but others ip solutions usually supporting one or two popular protocols.

DD-WRT is easily the most popular open-source router firmware today. It co-exists symbiotically with a list of about 700 reprogrammable router platform models produced by 97 hardware brands from 3 Com to Z Com. DD-WRT serving a community that chooses its powerful, simple and

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TABLE III. Project Quick Mesh Air Mesh Byzantium

Mesh Protocol BMX,OLSR BATMAN ADV OLSR

Common Project Project

OLSR

Meshnet

CJDNS

Freifunk

COMPARISON OF WIRELESS TECHNOLOGIES Addressing

Platform

URL

Ipv6 auto

OpenWRT

http://qmp.cat/

Ipv6 CJDNS Ipv6 zero conf Ipv4 custom

Linux

http://www.netlore.co.uk/airmesh/

Linux

http://project-byzantium.org/

OpenWRT

https://commotionwireless.net/

Linux, Android, OSX, more

https://projectmeshnet.org/

OpenWRT

http://freifunk.net/

Ipv6 CJDNS choose plug-in

VI.

REFERENCES “802.11s wireless mesh solution”, white paper NTT Docomo Technology reports, Calsoft labs, An ALTEN group company. [2] D. Eastlake, “Proposals for TGs”, IEEE 802.11-05/597r21. March 2006 [3] IEEE P802.11s/D0.01, March 2006. [4] Y. Matsumoto, J. Hagiwara, A. Fujiwara, H. Aoki, A. Yamada, S.Takeda, K. Yagyu and F. Nuno: “A Prospective Mesh Network BasedPlatform for Universal Mobile Communication Services,”IEICE GeneralConference, B-5-245, Mar. 2006 [5] A.Michael ,” Heterogeneous Wireless Mesh Network Technology Evaluation for Space Proximity and Surface Applications”, NASA Johnson Space Center, Houston, Tx, 77058 [6] J. Chroboczek, “The Babel Routing Protocol”, IETF RFC 6126 (Accessed 19th Novenber,2016, 12:58 am) URL: http://tools.ietf.org/html/rfc6126 [7] Self Organizing Wireless Mesh Networks (Accessed 12th December ,2016, 12:50 am) URL: http://research.microsoft.com/enus/projects/mesh/#software [8] The SPAN Project, (Accessed 14th December, 2016) URL: https://github.com/ProjectSPAN [9] Teensy Arduino & OpenWrt, (Accessed 14th December, 2016) URL: http://www.cse.dmu.ac.uk/~sexton/ENGD2003/openwrt/arduino teensyopenwrt.html [10] Air Mesh (Accessed 14th December, 2016) URL: http://www.netlore.co.uk/airmesh/?page=about [11] E. Erfanian, “Mobile Mesh Networks with the Raspberry Pi – Part 1”, 11 September, 2012 URL: http://www.ericerfanian.com/mobile-mesh-networks-with-theraspberry-pi-part-1/ (Accessed 14th December, 2016) [12] S. Venkat Mohan, Dr. N. Kasiviswanath ,” Routing Protocols for Wireless Mesh Networks”, International Journal of Scientific & Engineering Research Volume 2, Issue 8, August-2011 ISSN 2229-5518 [1]

CONCLUSION

The capital cost for implementing a mesh network in corporates, universities and industries is really low and selforganization, low complexity feature makes it more feasible in comparison to other wireless routing protocols. Its deployment in a wireless environment would need some mesh enabled (802.11s supported) routers to configure it as per required. Currently, using a 802.11s standard in a router and placing it in a mesh network would be totally dependent on the user. As it is an open source protocol which means anyone can implement it in any firmware above mentioned in the paper that he/she feels is easy to implement and readily available in the market. This paper ends up by giving in the depth insight into the 802.11s working architecture, its benefits, the bottlenecks of this protocol and its remaining inadequacy in congestion control, availability of channel in crowded environments and then gaining the access of the medium. Although HWMP tried to optimize these problems by using reactive and proactive protocol simultaneously, and these following points took decision according to the environmental constraints in a network. But as this protocol is still in its developing phase, future enhancements still are required in the: • • • • • • •

The Task group S of IEEE is still working hard to overcome the above mentioned challenges. And hopefully it is expected to be launched officially next year with all the problems resolved in this standard, and after that this protocol would be a worldwide standard used in all futuristic wireless devices.

MAC handling Multi-channel operation Seamless handover Intra-mesh congestion control End-to-end QOS limitations Power management Routing security and end-to-end security

[13] C. Jerry,H . Brett, A. Mehran,” Experimental evaluation of IEEE 802.11s path selection protocols in a mesh testbed”, Faculty of Informatics, University of Wollongong, 2010

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