Since the display horizontal scanning must be precise, the arrival time of lines will also need to be precise. ARINC 818 intends that timing parameters such as these be captured in an ICD specific to the video system. The authors of ARINC 818 built upon many years of combined experience of using FC to transport different video formats, and key implementation details are included in the specification, including examples of common analog formats. ARINC 818-2, ratified in December 2013, adds features to accommodate higher link rates, support for compression and encryption, networking, and sophisticated display schemes, such as channel bonding used on large area displays (LADs). Link rates: At the time the original ARINC 818 specification was ratified, the fiber-channel protocol supported link rates up to 8.5 gigabits per second (Gb/s). ARINC 818-2 added rates of 5.0, 6.375 (FC 6x), 12.75 (FC 12x), 14.025 (FC 16x), 21.0375 (FC 24x), and 28.05 (FC 32x) Gb/s. The 6x, 12x, and 24x speeds were added to accommodate the use of high-speed, bi-directional coax with power as a physical medium. The 5 Gbit/s rate was added to accommodate so implementation specific speeds supported by certain FPGAs. The specification also provides for non-standard link rates for bi-directional return path for applications such as camera control where high speed video links are not required. Compression and Encryption: ARINC 818 was originally envisioned as carrying only uncompressed video and audio. Applications such as high-resolution sensors, UAV/UAS with bandwidth limited downlinks, and data only applications drove the need to compress and/or encrypt a link. Sticking to a philosophy of maximum flexibility, the ARINC 818-2 calls for the ICD to specify implementation details for compression and encryption. The ARINC 818 protocol does not provide a means for compression and encryption, it simply provides flags to indicate that payload is compressed or encrypted. Switching: ARINC 818 was designed as a point-to-point protocol. Since many of the newer implementations of the ARINC 818 have multiple displays and or many channels of ARINC 818 (10 or more), switching has become more important. The new specification requires that active switching can only occur between frames. In effect, to prevent broken video frames, the switch must wait until the vertical blanking.