Requirements for a Distributed NFV Orchestration in a WMN-Based Disaster Network

Abstract

To provide an emergency communication infrastructure for rescue helpers and victims in the event of a disaster, the research project VirtO4WMN proposes to utilise a Wireless Mesh Network (WMN)-based disaster network. The network is constructed from battery-supplied wireless outdoor routers. By integrating the concept of Network Function Virtualisation (NFV), the network and service availability as well as their reliability are improved. For eliminating the singlepoint-of-failure of a centralised NFV orchestration the functionality of the NFV orchestration shall be distributed among the nodes in the WMN. For providing the best possible solution for a distributed NFV orchestration in a WMN-based disaster network, various requirements the orchestration must meet are defined and presented in this paper. The requirements are directly derived from the requirements of a WMN-based disaster network, which are also defined in this paper.

High Throughput WMN for the Communication in Disaster Scenario

“… Second, a new cluster is built only if two or more cluster members provide a gateway functionality to adjoining clusters. This constrain is defined to avoid the partitioning of the WMN (network resilience [8]). According to the above defined optimisation objectives and constrains, if the WMN topology in Figure 13a is considered, where each router can communicate with eight neighbour routers (routers within its transmission range) and is equipped with two wireless interfaces, the optimal cluster size can be determined using the following steps:  First, neighbouring routers of router A are separated into two groups and assigned to one of its two interfaces depending on their location within the network.…”

Possible Challenges and Appropriate Measures for a Resilient WMN-Based Disaster Network

“…According to [4], the resilience enabler medium diversity provides choices among alternative physical media and therefore increases the connectivity through different available paths. This aspect cannot be provided by the WMN-based disaster network since it only utilises the Wi-Fi technology as described in [2]. Due to the limited physical range of a Wi-Fi signal, a failing node might create a network partition if its geographical location, and thereby its wireless links, was critical.…”

“…The utilisation should therefore be as simple as possible and shall not require any special equipment. For this reason, as described in [2], the access for the users is based on the Wi-Fi technology since it is a common technology. Regarding the normal state of the disaster network, it needs to be ensured that the access network, which is realised through Wi-Fi-based access points (APs), is available and spanning the complete geographical region to ensure the connectivity for the users and thus the usability of the disaster network itself.…”

“…The provisioning of an emergency communication infrastructure for rescue helpers and victims in case of existing communication infrastructures being destroyed by natural disasters (such as earthquakes and floods) or manmade disasters (such as persistent power outages) is assumed to be crucial. For this reason, [1] proposes the deployment of a disaster network for providing such an emergency communication infrastructure, while [2] further specifies the network. The disaster network is intended to be constructed from battery-supplied multi-radio wireless outdoor routers being deployed in the disaster environment by the first responders.…”

“…The disaster network needs to operate and provide its functionality to the user at any time to remain available and thus usable. This aspect is defined in more detail in [2], which presents various requirements for the WMN-based disaster network. Among other requirements, a continuous working infrastructure as well as the support of a flexible and dynamic infrastructure are crucial for the disaster network.…”