Google is great for many things; however, when defining application delivery network technology, it can be argued that it does more harm than good. As such, researching the concept of an application delivery network (ADN) can be a frustrating and exhausting process if you don’t already understand industry buzzwords. It can be difficult to weed through this technical networking jargon, because it often leads to definitions explained by more technical networking jargon (see below):
We thought it was about time to take matters into our own hands and make up for the shortcomings of our usually-reliable search engines and Wikipedia. Here, in one place, we walk you through the trail of the most common ADN buzzwords from start to finish so you don’t have to go it alone.
1. Data Packet:
A data packet is an information request that travels from a server through a network to get to an end user, and then back again. When a user clicks a link to load a page, for instance, a data packet request is sent for the necessary elements to load.
2. Network Latency:
Latency is the time it takes for a data packet to get from the server to the end user, or between two points on the Internet. Latency increases as the distance between the server and the end user increases. The greater the latency, the longer it takes the site to load.
3. IP Address:
An Internet protocol address, or IP Address, is a sequence of four numbers separated by dots (i.e. 220.127.116.111). It is unique to a given network, computer, or other device connected to the Internet. IP addresses enable devices to communicate using the rules, or protocols, of the many networks that make up the entire Internet. IP addresses can either be static and unchanging, or dynamic and temporary, and are controlled by ISPs, or Internet service providers.
4. TCP Optimization:
TCP Optimization is the method in which Transmission Control Protocol (TCP/IP), or the part of the Internet protocol that ensures reliable and error-checked data packet delivery, is “tuned” over networks with high bandwidth andlatency. An intelligently optimized TCP can result in improved performance and load websites up to 10 times faster.
5. Open Systems Interconnection (OSI) Layers:
Open Systems Interconnection, or OSI, is a framework around which software and digital communication products may be created to interoperate, or work and communicate seamlessly, with one another. TechTarget defines the significance of the 7 OSI Layers, or separate variables, which are required for successful interoperation:
- Application Layer
- Presentation Layer
- Session Layer
- Transport Layer
- Network Layer
- Data-Link Layer
- Physical Layer
6. Local Area Network (LAN):
A Local Area Network, or LAN, is a network of workstations in a small geographical area that may be connected to one another through phone lines and/or radio transmissions.
7. Wide Area Network (WAN):
A Wide Area Network, or WAN, is a network of LANs combined to form a single network entity over a dispersed geographical area. They are common in universities and enterprises where a group of people (i.e. students or employees) need to access a network from many locations, be it cities, states, or countries. The network manager has control over who can access the WAN and what data may be sent.
8. WAN Optimization Controller (WOC):
A WAN Optimization Controller, or WOC (also called a WAN Accelerator), is the specialized hardware and software that make it possible to speed up data transmission to users through a WAN. It does this by affecting each of the 7 OSI Layers, and partially by TCP Optimization.
9. Data Center:
A data center is a clump of physical servers that virtually store, manage, and transmit data. Typically, data centers are owned and operated by the enterprises or organizations that store their information in them and maintain the connected network (i.e. WAN).
10. Static Content:
Static content can be cached, or stored in PoPs, to easily serve up to users across the globe. Static content is the same for all users and includes site elements like text, images, and embedded videos.
11. Points of Presence (PoPs):
PoPs, or Points of Presence, are the physical locations of servers. They act as local access points to receive data and content from far away, store it, and mirror the original to a local user whenever that data is requested. PoPs are an essential part of a delivery network because they allow static content and information hosted far away to be stored close to end users all over the globe, which in turn provides a more uniform user experience and faster page load times.
12. Dynamic Content:
Dynamic content cannot be cached, or stored in PoPs, because it is unique to a given user and session. For example, ecommerce shopping carts, employee benefits documents, stock quotes, computer game, and even a user’s Twitter feed constitute dynamic, changing content.
An application is any interactive software operation that delivers dynamic content to a user based on his or her unique commands. On a website, an application is said to serve up dynamic content.
14. Load Balancing:
Load balancing is the process by which computers, servers, cloud storage devices, etc. distribute incoming and outgoing data to “balance” the load and ensure efficient data delivery to users. Reducing load ensures consistent web performance across all users accessing the site simultaneously.
Fault-Tolerance is a performance and security feature of a computer component, system, or network. It signifies that there is a backup procedure in place to continue proper operation without any downtime if a component or procedure fails.
16. Application Delivery Controller (ADC):
An ADC is a highly specialized component that load balances network applications. An ADC’s fault-tolerance allows it to recognize when a single server or group of servers is down and therefore send requests to ones that are working. This averts any errors or delays for the user, and therefore optimizes application delivery performance.
17. Application Delivery Network (ADN):
An application delivery network, or ADN, is a network solution for optimizing users’ experiences as they interact with website applications that serve up dynamic content. Several factors are incorporated in an ADN solution, including (but not limited to) application delivery controllers (ADCs) that load balance and orchestrate data packet signals coming from users engaging in the site experience, to the data center or server(s), and then back to the user again. ADNs limit the amount of latency as well as improve overall application performance partially by optimizing the 7 OSI Layers and the TCP/IP Protocol. These are part of a WAN Optimization Controller, which is another element of an ADN solution.
In sum, we can now better understand ADN technology as defined by Google and Wikipedia: an ADN is a suite of technologies that, when deployed together, provide application availability, security, visibility, and acceleration.
Are there other ADN or CDN buzzwords you want to know about? Take a look through our Web Performance Glossaryto decode even more terms and let us know in the comments below what others you’d like to see.