Although the fact that VPN provide a safe and reliable transfer of customers’ data,
but the basic configurations on which they depend VPN and transport networks of
asynchronous (ATM) and Frame Relay networks (FR).Link, that depend on them these
te
chniques are relatively slow and cause a delay in time
With the rapid growth of the Internet and increase the load on the network in terms
of users and providers of service to look for ways of effective and fast routing packets of
data while ensuring quality of service began(QoS)and class of service(Cos)and secure
management and engineering movement(traffic) on the network and appeared the multiswitch
tags of the Protocol(MPLS)standard modern technique verify the previous
requirement safter she was initially way to improve the transmission speed routers.
This paper presents an analytical study on improving the performance of virtual
private networks using multi-protocol label switching( MPLS_VPN), by improving routing
operations on the third level, minimizing the delays and complexity resulting from the
routing on full internal routers in the traditional technical protocols settings and limited to
Edge routers in networks MPLS_VPN.
OPNET was used simulation software to get the results of the analysis and
simulation of new technology and compare it with the old technology.
The desire to improve the overall performance of IP network leads to designing new
QoS achitectures. The new Enhancement in providing quality of service (QoS) on the
Internet is based on the Different Services (DiffServ). DiffServ divides traffic i
nto small
classes and allocates network resources on a per-class basis. In this architecture, packets
are marked with different DiffServ code points (DSCP) at edge routers, and the priority for
packets is given via the value of this field. On the other hand, MPLS is a fast forwarding
mechanism that depends on Label's. The main advantage of MPLS is its support for traffic
engineering which results in best utilization of network's resources like link capacity. The
integration of using MPLS (as a forwarding mechanism) with DiffServ (as a QoS
mechanism) offer high Quality of service especially for real time applications (such as
VoIP, Video Conference).
We evaluate the performance of MPLS-DiffServ networks in our research. We study
QoS metrics as delay, variation of delay, upload response time, link utilization, packet loss
for several kinds of traffic (Voice, Video, FTP) by using OPNET Simulator and we
showed its superiority over MPLS network and pure IP ones. We compare our results with
MPLS networks and pure IP ones. Our results showed superiority of MPLS-DiffServ over
other kinds of networks. This is clear in decreasing delay ,delay variation, upload response
time, queuing delay, reduction of lost packets and best utilization of link capacity.
With the widespread of new fast networks and need for critical application, survivability,
reliability and quality of service became an sensational issue. Recovery mechanism used by IP
network spent a lot of time from several seconds to minutes. Th
is causes large drop in data
packages. MPLS is a next generation backbone architecture, which can speed up packet forwarding
to destination by label switching especially with its traffic engineering capability. MPLS recovery
mechanisms are increasing in popularity because they can guarantee fast restoration and high QoS
assurance.
We simulated in our research several scenarios for link failure using fast reroute technology
in MPLS network's using Opnet. Results lead us to consider this technique successful in limiting
delay and packet drop in recovery cycle.
