Welcome to Infoarch Resources
Infoarch Multimedia Terms
Disclaimer: This section is intended as a quick reference for those with technical background only. Advice posted in this area may be simplified; certain key steps may be neglected with the assumption that you know what you are doing. If you don't, please consult your Infoarch representative.
| Multimedia Term | Description |
|---|---|
| Aspect Ratio | The width/height ratio of a television set or movie screen. Most television sets have a 4:3 aspect ratio. Wide screen television sets have a 16:9 aspect ratio. |
| Bidirectional (B) Frame | One of the three picture types in MPEG compression. B frames are coded in relation to previous or subsequent I or P frames. B frames do not serve as a reference for other frames |
| Data Rate | The speed of the data stored on a type of media, usually expressed in bits per second or bytes per second. |
| Data Transfer Rate | The transfer rate of the storage media itself. VCD transfer rate is 1.2MB. |
| Downmix | The process of converting a multi-channel audio track to two- or one-channel track. |
| Dolby Digital | Also known as AC-3. A high-quality, bandwidth-efficient perceptual audio coding system originally developed by Dolby Laboratories for multi-channel digital sound in the cinema. It can be used in broadcast, cable, film, and recorded media in both professional and consumer applications. Dolby Digital is one of the main audio formats used in DVD. |
| Dolby Surround | The consumer version of the original analog Dolby multi-channel film sound format. |
| Drop Frame Time Code | A mode of operation when playing back NTSC video. In NTSC, the actual frame rate is roughly 29.97 fps. When the time code indicates 1 hour of film, 1 hour, 3 seconds, and 18 frames worth of actual time has elapsed, or a discrepancy of 108 frames. Some encoders resolve the time code discrepancy by dropping two frame numbers every minute, on the minute, except the tenth minutes. |
| DTS (Digital Theater Sound) | An audio encoding technology developed for theaters. DTS was developed to compete with Dolby Digital and is an additional audio format for DVD. |
| GOP (Group of Pictures) | A GOP is a single MPEG video random access unit. |
| Intra (I) Frame | A key reference frame in the MPEG compression algorithm. I Frames are one of the three types of frames used in MPEG compression. They contain all the data needed to represent an entire frame, hence are referred to as key reference frames. |
| Linear PCM | A non-compressed digital audio format. The DVD specification allows for 16 to 24 bit Linear PCM audio sampled at 48 or 96 kHz. |
| MP3 | MP3 is the MPEG audio layer 3 standard. Layer 3 is one of three coding schemes (layer 1, 2, and 3) for the compression of audio signals defined by the MPEG committee. Layer 3 uses perceptual audio coding and psychoacoustic compression to remove the redundant parts of a sound signal. It also adds an MDCT (Modified Discrete Cosine Transform) that implements a filter bank, increasing the frequency resolution 18 times higher than that of MPEG audio layer 2. |
| MPEG-1 | ISO/IEC standard designed for low bandwidth of compressed digital video and audio. VCD uses this format with resolution of 352x288@25fps (PAL) or 352x240@29.97fps (NTSC). |
| MPEG-2 | ISO/IEC standard designed for transmission of high bandwidth compressed digital video and audio such as that used by broadcast television. DVD uses this format with resolution of 720x576@25fps (PAL) or 720x480@29.97fps (NTSC). |
| MPEG-4 | ISO 14496 is an ISO/IEC standard developed by MPEG (Moving Picture Experts Group). Although defined as one standard, MPEG-4 is actually a set of compression/decompression formats and streaming technologies that address the need for distributing rich interactive media over narrow and broadband networks. |
| MPEG Audio | Multi-channel digital audio defined by the MPEG specification. MPEG-1 Layer 2 is compressed using perceptual coding. It has a sample rate of 32, 44.1, and 48 kHz at 16 bits and can contain mono or stereo streams. MPEG-1 Layer 3 supports variable sample rate. MPEG-2 audio is an extension of MPEG-1 audio. It supports low bit rates and up to 7.1 audio channels. |
| Multiplexing | Combining two or more data streams together into a single stream. |
| Predicted (P) Frame | Frames used in MPEG compression which are coded in relation to the nearest previous I or P frame. P frames serve as a prediction reference for B frames and future P frames. |
| SDDS (Sony Dynamic Digital Sound) | An audio encoding technology developed by Sony for multi-channel audio in cinemas and theaters. SDDS was developed to compete with Dolby Digital and is an optional audio format for DVD. |
| S-Video | A video signal that carries separate luminance and chrominance signals. |
| SMPTE EBU Time Code | A standard for a signal recorded on videotape to uniquely identify each frame of the video signal. It is used to control editing operations. (SMPTE stands for Society of Motion Picture and Television Engineering). |
Infoarch Networking Terms
This section is intended as a quick reference for those with technical background only. Advice posted in this area may be simplified; certain key steps may be neglected with the assumption that you know what you are doing. If you don't, please consult your Infoarch representative.
| Networking Term | Description |
|---|---|
| Amplifier | A network component, also known as a repeater. Amplifiers increase the power of a signal when it is lost due to attenuation. They allow signals to cover greater distances in a LAN environment. |
| Application Layer | The seventh layer in the OSI model. The Application layer defines program-to-program communication, or how applications access network services. Services defined by the Application layer include file transfer, job transfer, and terminal emulation. |
| ATM | Broad bandwidth (155 Mb). ATM can be implemented either as a backbone solution or as an entire network solution. In the backbone scenario, ATM is used to connect departments, floors, or any part of the organization that is distant from the main server center. In the network scenario, ATM is used as the entire LAN, WAN, or MAN. LAN Emulation (LANE) is used in these types of networks to give an Ethernet feel to the network. This emulation is easier to implement than IP emulation over ATM and is much more popular. |
| Bandwidth | The amount of data that can be transmitted in a fixed amount of time. For digital devices, the bandwidth is usually expressed in bits per second or bytes per second. For analog devices, the bandwidth is expressed in cycles per second, or Hertz (Hz). |
| Bridge | A network component that connects two LANs, thus extending the range of the network. Bridges check data and forward them across LANs. |
| Broadband | A single wire or network pipe that has sufficient bandwidth to carry large amounts of data simultaneously. |
| Broadcast | When data is sent simultaneously to all stations on a network. |
| Brouter | A network component that serves as both a Bridge and a Router. |
| Buffer | Space allocated on a system's Random Access Memory (RAM) where data is stored temporarily until it is transferred to another part of the system. |
| Bus Topology | A LAN network structure in which all stations (nodes) are connected to the same cable. Data is transmitted up and down this single cable. |
| Cable Modem | A modem that connects home networking systems (computer + TV) to cable TV networks, bypassing traditional phone networks. Cable TV networks use a coaxial cable or HFC infrastructure. |
| Circuit Switching | A communication technology in which a dedicated channel (circuit) is established for the duration of a transmission. |
| Collisions | In an Ethernet network, every host connected to the network can transmit at any time. This may result in two hosts transmitting at the same time. If a collision between packets is sensed by both hosts, their NICs (Network Interface Cards) perform a Back Off - a transmission time-out. Since the length of the back-off is randomly determined, in most cases when the time-out has elapsed both NICs will be able to re-transmit without interfering with each other. There is always a chance that another host will try to send a packet, causing the back-off procedure to start again. |
| Coaxial Cable | Copper cable that consists of a central wire surrounded by insulation and then a grounded shield of braided wire. Coaxial wire is widely used by the cable television industries. It is less prone to interference than regular wire cables. Most older Ethernet networks also use coaxial cable. |
| Connectionless vs Connection-oriented Protocols | When using a connectionless protocol, hosts send data without establishing a connection with the recipient. The host does not know if the data arrives at its destination or not. In contrast, connection-oriented protocols require a designated path to be established between the sender and receiver before any messages are transmitted. |
| Dial-Up Access | When computer devices hook up to a network via modem and public phone system on a pay-per-time basis. Usually, dial-up connections offer limited bandwidths. The alternative is a leased line that offers continuous access at a constant bandwidth to a network. |
| DSL (Digital Subscriber Lines) | A general acronym relating to Digital Subscriber Lines. The two main types are ADSL (Asynchronous) and SDSL (Synchronous). DSL modulate data over copper wires. Also known as 'last mile' technologies because they are used to connect only between telephone switching stations to a home or office, not between switching stations. |
| E1/T1 | In the United States, a T1 service is a framed communication protocol that delivers a two-way connection at 1.544 Mbits/s each way. In many other countries, the equivalent of T1 is a service called E1 - a two-way connection at 2.048 Mbit/s. |
| FDDI (Fiber Distributed Data Interface) | A set of ANSI protocols for sending digital data over fiber optic cable. FDDI networks are token-passing networks. They support data rates of up to 100 Mbps. FDDI networks usually serve as backbones for wide-area networks. FDDI-2 is an extension of FDDI that supports the transmission of voice and video too. |
| FTP (File Transfer Protocol) | A protocol that defines the transfer of files over the Internet. |
| Hub | A networking component that enables the common connection of devices to a network. Hubs are usually used to connect nodes in local area networks. Active hubs can regenerate data over the network, whereas passive hubs only transfer information. |
| Jitter | Data packets, in general, are not sensitive to how long it takes for them to arrive or when they arrive in relation to the preceding or subsequent packets. The delay added by the network is called latency. The difference over time between the latencies of different packets is called jitter. |
| IP (Internet Protocol) | The protocol that defines how packets are formatted and addressed when sending data over the Internet. The IP frame header contains routing information and control information associated with datagram delivery. IP is part of the TCP/IP group of protocols. |
| IP Multicast | To send information over the Internet to a group of computers that share the same IP address. |
| Local Area Networks (LAN) | A network that covers a small geographical area. |
| Latency | The amount of time it takes a packet to travel from source to destination. Together, latency and bandwidth define the speed and capacity of a network. |
| Leased Line | A permanent connection to a network that guarantees constant bandwidth and network access. Leased lines cost a fixed monthly fee. |
| Modem | A network interface device that allows computers to send and receive data over telephone lines. |
| Quality of Service (QoS) | Quality of Service refers to the way data is transmitted between two hosts on a network. Networking protocols that offer QoS make sure that when information needs to be communicated, the sender requests a designated path with the network for a connection to the destination. The sender specifies the type, speed, and other attributes of the call, which determine and guarantee the end-to-end quality of service. |
| Packet Switching | A networking technology in which messages are divided into packets before they are sent. Each packet is transmitted individually and can even follow different routes to its destination. Once all the packets forming a message arrive at the destination, they are recompiled into the original message. Packet switching is more efficient and robust for data that can withstand some delays in transmission, such as e-mail messages and Web pages. |
| Router | A networking device that connects different types of networks. Routers know how to direct data between networks that use different architectures and protocols. |
| RTP (Real-Time Transport Protocol) | An Internet protocol that defines the transmission of real-time data, for example, audio and video. RTP provides mechanisms for the sending (server) and receiving applications to support streaming data. RTP usually runs on top of the UDP protocol. |
| Star Topology | A local-area network (LAN) in which all nodes (stations) are connected to a central device. |
| Streaming | A technique for transferring data so that it is received as a continuous real-time stream. |
| TCP (Transmission Control Protocol) | TCP is one of the main protocols in TCP/IP networks. TCP defines the way two hosts establish a connection and exchange streams of data. TCP guarantees delivery of data and also guarantees that packets will be delivered in the same order in which they were sent. |
| TCP/IP | A set of protocols designed by the US Department of Defense for transferring data between networks. |
| UDP (Universal Data Protocol) | A transfer protocol that allows any station on a network that possesses a standard network card to transmit or receive information, without the need for a special interface card. UDP is mainly used to broadcast messages over a network. |
| Virtual Private Network (VPN) | A network dedicated to a specific user or group of users that is part of a public network. For example, there are a number of systems that enable users to create dedicated networks using the Internet as the backbone for transporting data. |
| VLANS | Virtual Local Area Networks are networks that allow any user, no matter where they are, to log on to their home network. |
| WAP (Wireless Application Protocol) | A protocol that defines delivery and access of information to wireless devices. |
| Wide Area Network (WAN) | A network that covers large geographical areas by connecting many local area networks together. |
Infoarch TCP/UDP Ports
We have included a generalized list for your perusal, you should possess sufficient knowledge of TCP, IP and UDP to effectively make use of this table. For example, port 53 is used by DNS, but TCP and UDP 53 are used differently, which we will not go into details here.
This is not a comprehensive list, showing only the ports used by Internet well known services.
Firewall Tips: To maximize protection against intruder, configure your gateway to block all incoming and outgoing traffics except from and to certain sites specifically chosen.
For ease of administration, you may choose to allow all traffic to get through except certain specific ports. For example, you may want to block port 4000 to prevent your users from using ICQ, which can be a resource hog
Port List
| Port Number | Service |
|---|---|
| 1 | tcpmux |
| 5 | rje |
| 7 | echo |
| 9 | discard |
| 11 | systat |
| 13 | daytime |
| 15 | netstat |
| 17 | qotd |
| 18 | send/rwp |
| 19 | chargen |
| 20 | ftp-data |
| 21 | ftp |
| 22 | ssh, pcAnywhere |
| 23 | Telnet |
| 25 | SMTP |
| 27 | ETRN |
| 29 | msg-icp |
| 31 | msg-auth |
| 33 | dsp |
| 37 | time |
| 38 | RAP |
| 39 | rlp |
| 42 | nameserv, WINS |
| 43 | whois, nickname |
| 49 | TACACS, Login Host Protocol |
| 50 | RMCP, re-mail-ck |
| 53 | DNS |
| 57 | MTP |
| 59 | NFILE |
| 63 | whois++ |
| 66 | sql*net |
| 67 | bootps |
| 68 | bootpd/dhcp |
| 69 | Trivial File Transfer Protocol (tftp) |
| 70 | Gopher |
| 79 | finger |
| 80 | www-http |
| 88 | Kerberos, WWW |
| 95 | supdup |
| 96 | DIXIE |
| 98 | linuxconf |
| 101 | HOSTNAME |
| 102 | ISO, X.400, ITOT |
| 105 | cso |
| 106 | poppassd |
| 109 | POP2 |
| 110 | POP3 |
| 111 | Sun RPC Portmapper |
| 113 | identd/auth |
| 115 | sftp |
| 117 | uucp |
| 119 | NNTP |
| 120 | CFDP |
| 123 | NTP |
| 124 | SecureID |
| 129 | PWDGEN |
| 133 | statsrv |
| 135 | loc-srv/epmap |
| 137 | netbios-ns |
| 138 | netbios-dgm (UDP) |
| 139 | NetBIOS |
| 143 | IMAP |
| 144 | NewS |
| 152 | BFTP |
| 153 | SGMP |
| 161 | SNMP |
| 175 | vmnet |
| 177 | XDMCP |
| 178 | NextStep Window Server |
| 179 | BGP |
| 180 | SLmail admin |
| 199 | smux |
| 210 | Z39.50 |
| 218 | MPP |
| 220 | IMAP3 |
| 259 | ESRO |
| 264 | FW1_topo |
| 311 | Apple WebAdmin |
| 350 | MATIP type A |
| 351 | MATIP type B |
| 363 | RSVP tunnel |
| 366 | ODMR (On-Demand Mail Relay) |
| 387 | AURP (AppleTalk Update-Based Routing Protocol) |
| 389 | LDAP |
| 407 | Timbuktu |
| 434 | Mobile IP |
| 443 | ssl/https |
| 444 | snpp, Simple Network Paging Protocol |
| 445 | SMB |
| 458 | QuickTime TV/Conferencing |
| 468 | Photuris |
| 500 | ISAKMP, pluto |
| 512 | biff, rexec |
| 513 | who, rlogin |
| 514 | syslog, rsh |
| 515 | lp, lpr, line printer |
| 517 | talk |
| 520 | RIP (Routing Information Protocol) |
| 521 | RIPng |
| 522 | ULS |
| 531 | IRC |
| 543 | KLogin, AppleShare over IP |
| 545 | QuickTime |
| 548 | AFP |
| 554 | Real Time Streaming Protocol |
| 555 | phAse Zero |
| 563 | NNTP over SSL |
| 575 | VEMMI |
| 581 | Bundle Discovery Protocol |
| 593 | MS-RPC |
| 608 | SIFT/UFT |
| 626 | Apple ASIA |
| 631 | IPP (Internet Printing Protocol) |
| 635 | mountd |
| 636 | sldap |
| 642 | EMSD |
| 648 | RRP (NSI Registry Registrar Protocol) |
| 655 | tinc |
| 660 | Apple MacOS Server Admin |
| 666 | Doom |
| 674 | ACAP |
| 687 | AppleShare IP Registry |
| 700 | buddyphone |
| 705 | AgentX for SNMP |
| 901 | swat, realsecure |
| 993 | s-imap |
| 995 | s-pop |
| 1062 | Veracity |
| 1080 | SOCKS |
| 1085 | WebObjects |
| 1227 | DNS2Go |
| 1243 | SubSeven |
| 1338 | Millennium Worm |
| 1352 | Lotus Notes |
| 1381 | Apple Network License Manager |
| 1417 | Timbuktu |
| 1418 | Timbuktu |
| 1419 | Timbuktu |
| 1433 | Microsoft SQL Server |
| 1434 | Microsoft SQL Monitor |
| 1494 | Citrix ICA Protocol |
| 1503 | T.120 |
| 1521 | Oracle SQL |
| 1525 | prospero |
| 1526 | prospero |
| 1527 | tlisrv |
| 1604 | Citrix ICA, MS Terminal Server |
| 1645 | RADIUS Authentication |
| 1646 | RADIUS Accounting |
| 1680 | Carbon Copy |
| 1701 | L2TP/LSF |
| 1717 | Convoy |
| 1720 | H.323/Q.931 |
| 1723 | PPTP control port |
| 1755 | Windows Media .asf |
| 1758 | TFTP multicast |
| 1812 | RADIUS server |
| 1813 | RADIUS accounting |
| 1818 | ETFTP |
| 1973 | DLSw DCAP/DRAP |
| 1985 | HSRP |
| 1999 | Cisco AUTH |
| 2001 | glimpse |
| 2049 | NFS |
| 2064 | distributed.net |
| 2065 | DLSw |
| 2066 | DLSw |
| 2106 | MZAP |
| 2140 | DeepThroat |
| 2301 | Compaq Insight Management Web Agents |
| 2327 | Netscape Conference |
| 2336 | Apple UG Control |
| 2427 | MGCP gateway |
| 2504 | WLBS |
| 2535 | MADCAP |
| 2543 | sip |
| 2592 | netrek |
| 2628 | DICT |
| 2727 | MGCP call agent |
| 2998 | ISS Real Secure Console Service Port |
| 3000 | Firstclass |
| 3031 | Apple AgentVU |
| 3128 | squid |
| 3130 | ICP |
| 3150 | DeepThroat |
| 3264 | ccmail |
| 3283 | Apple NetAssitant |
| 3288 | COPS |
| 3305 | ODETTE |
| 3306 | mySQL |
| 3389 | RDP Protocol (Terminal Server) |
| 3521 | netrek |
| 4000 | icq, command-n-conquer |
| 4321 | rwhois |
| 4333 | mSQL |
| 4827 | HTCP |
| 5004 | RTP |
| 5005 | RTP |
| 5010 | Yahoo! Messenger |
| 5060 | SIP |
| 5190 | AIM |
| 5423 | Apple VirtualUser |
| 5500 | securid |
| 5501 | securidprop |
| 5631 | PCAnywhere data |
| 5632 | PCAnywhere |
| 5800 | VNC |
| 5801 | VNC |
| 5900 | VNC |
| 5901 | VNC |
| 6000 | X Windows |
| 6112 | BattleNet |
| 6502 | Netscape Conference |
| 6667 | IRC |
| 6670 | VocalTec Internet Phone, DeepThroat |
| 6699 | napster |
| 6776 | Sub7 |
| 6970 | RTP |
| 7007 | MSBD, Windows Media encoder |
| 7070 | RealServer/QuickTime |
| 7648 | CU-SeeMe |
| 7649 | CU-SeeMe |
| 7778 | Unreal |
| 8010 | WinGate 2.1 |
| 8080 | HTTP |
| 8181 | HTTP |
| 8383 | IMail WWW |
| 8530 | WSUS |
| 8875 | napster |
| 8888 | napster |
| 10008 | cheese worm |
| 11371 | PGP 5 Keyserver |
| 13223 | PowWow |
| 13224 | PowWow |
| 14237 | Palm |
| 14238 | Palm |
| 18888 | LiquidAudio |
| 21157 | Activision |
| 23213 | PowWow |
| 23214 | PowWow |
| 23456 | EvilFTP |
| 26000 | Quake |
| 27001 | QuakeWorld |
| 27010 | Half-Life |
| 27015 | Half-Life |
| 27960 | QuakeIII |
| 30029 | AOL Admin |
| 31337 | Back Orifice |
| 32773 | rpc.ttdbserverd |
| 32776 | rpc.spray |
| 32777 | rpc.walld |
| 32779 | rpc.cmsd |
| 38036 | timestep |
| 40193 | Novell |
| 41524 | arcserve discovery |
| 45000 | Cisco NetRanger postofficed |