Network architecture from Wan to sd-wan edge devices

Today's applications and network architecture need a new approach , cloud 、 The emergence of virtualization and as a service model has overturned the traditional enterprise network . In this cloudy world , How to reorganize the wide area network and how to unify the connection .

Management trends and practices are changing , The network operation and maintenance team is facing increasing pressure , Need to simplify the network 、 Make it more flexible 、 Centralized control , At the same time, you need to optimize application performance .

modern WAN Traditional applications and delay sensitive real-time services must be supported （ Such as IP voice (VoIP) Video conferencing ） The connection of .

This paper will discuss the popularization of Science WAN（ Wide area network ） Network challenges and opportunities in —— Where does it start , How it developed and why SD-WAN Provide those opportunities for the future .

Wan communication

1. Router

Traditionally , Routers are usually enterprises （ family ） Edge provides WAN connectivity , These routers lack policy based control and automation, as well as the intelligence of cloud connectivity . Routers generally do not consider the details of the underlying transmission infrastructure ; This lack of abstraction limits their flexibility in connecting to the cloud .

2. Dedicated link 、MPLS and VPN

MPLS And dedicated line services are private connections provided by service providers . These services provide predictable performance , And provide guaranteed flow performance and delivery SLA. Unfortunately , They are often much more expensive than broadband Internet services , The benefits of broadband services are better than MPLS And private line services are easier to obtain and deploy .

although MPLS Provides key benefits , Including scalability 、 performance 、 Improve bandwidth utilization and reduce network congestion , But it's not for clouds and SaaS The design of the . This is mainly because all traffic must be returned / Hairpin , Increased impact of delays on the end user experience .

VPN Links provide an economical solution 、 Secure remote connection alternatives . For the sake of safety , These connections establish an encrypted tunnel over the public Internet , adopt VPN The client connects remote users to the corporate network . although VPN Continue to be widely used , But this technology still faces bandwidth 、 Scalability and security challenges .

Typical branch site to data center site VPN Connect

3. WAN optimization

MPLS Cost and application specific requirements （ for example , Delay sensitivity ） It is an early factor to promote WAN optimization on international links . With the rise of real-time voice and video communication , Services are highly sensitive to latency and jitter , This is a popular feature .

WAN Optimization includes basic inline compression and a series of TCP Optimize 、 Data deduplication 、 Application agents and protocol specific optimizations . The fact proved that , These functions can effectively manage delay sensitive applications and in WAN Transmitting a large amount of data in , Especially for global transmission .

Deploy WAN Optimization solutions are complex , And you need to have physical devices at each end of the connection . These systems are limited to application proxy support and encryption applications , for example TLS And based on SSL Solutions for . Wan optimized devices will not improve the user experience outside the traditional office environment .

The network of today's Network 、SD-WAN、 Here comes the superhero of software defined Wan and LAN

4. SD-WAN

If someone asks how to define SD-WAN Or ask WAN and SD-WAN The difference between ？

The answer is SD-WAN Related to the application performance and experience quality of end users .

as time goes on , Applications become smarter , And less frequently on WAN links . Services are beginning to move to the cloud （ for example SaaS）, And the public Internet has become more economical and available . Besides ,SD-WAN Make broadband Internet connections more reliable , Higher performance , Safer for business communications and services ; They are no longer seen as just a best effort connection . Because it has nothing to do with transmission ,SD-WAN You can focus on the performance of your application , It uses application recognition 、 Bandwidth aggregation 、 Dynamic path selection , At the same time, it provides security and minimizes routing complexity . The following figure is the architecture diagram of software defined network ：

SD-WAN Allow enterprises to use software to define networks (SDN) practice , Put the data 、 The control and management planes are separated .

SD-WAN Key indicators include ：

• Transmission independence
• Security coverage
• Application performance
• simplicity , Used to manage 、 A single management portal for configuration and troubleshooting