PC over IP (PCoIP) is a remote display protocol that Teradici developed for delivering remote desktops and applications to endpoints.
PCoIP works by rendering client desktops on a network or cloud server. The desktop's pixels are then compressed, encrypted and then transmitted to the client device. The client then decrypts and renders the desktop view for the user.
PC over IP uses the User Datagram Protocol (UDP), an alternative to the Transmission Control Protocol (TCP). UDP features process-to-process communication and uses a loss-tolerant, low-latency connection to link an application to the internet. PCoIP delivers bitmaps, which define where a pixel appears on the screen and what color it should be, by encoding them on a remote host and then streaming the data to the client. It transmits only regions of the screen that change from frame to frame. From the endpoint perspective, it's almost as if the client is watching a real-time movie of the desktop's activities.
The protocol can handle multimedia and graphics-heavy applications, but it does increase the CPU load on the remote host.
Creation and development
Teradici created the PCoIP protocol and debuted it in 2007.
Initially, PCoIP was a hardware-based desktop virtualization product designed around a blade server that rendered desktop images, and a client device that somewhat resembled a hockey puck. The client device was equipped with a proprietary chip that enabled the use of PCoIP communications between the client and server.
PCoIP initially depended on proprietary hardware, but Teradici eventually created a software version of the PCoIP protocol. Teradici licensed the software to VMware in 2008. VMware used PCoIP to deliver virtual desktops with what was then called VMware View, now Horizon.
Core features and components
PCoIP has evolved over the years, especially with regard to its port requirements.
For example, VMware supports PCoIP over both TCP and UDP. In VMware Horizon View 4.0 and 4.1, PCoIP uses port number 500002. In VMware Horizon View 4.5, VMware changed the port number to 4172. Similarly, the PCoIP management console initially used TCP port 50000, but VMware changed it to port number 5172 in version 2.0 of the management console.
PCoIP is best known for its use in VMware Horizon View, but Teradici continues to offer remote workstation cards, zero clients, graphics agents and clients that allow organizations to use PCoIP in data center and cloud deployments.
Benefits and drawbacks
The primary benefit to PCoIP is that it allows an organization to avoid using PCs as client endpoints, relying instead on thin clients or zero clients. Thin clients and zero clients cost less than PCs and require almost no maintenance. Furthermore, thin clients and zero clients tend to be more secure than PCs because they are not dependent on a local operating system.
Conversely, PCoIP depends on a network or a cloud server to render desktops. As a result, if a problem with server-side rendering pops up, it could affect every virtual desktop user.
One of the most common problems with PCoIP is latency. Graphics-intensive applications may not display properly if sufficient bandwidth is not available or if the server becomes bogged down with user requests.