Lantronix S3220 Series User Guide Rev J PDF 34.75 MB - Page 690

Transition Networks ION x222x / x32xx User Guide STP (Shielded Twisted Pair). UTP is used in Ethernet 10Base‐T and 100Base‐T networks, as well as in home and office telephone wiring. The twist in UTP helps to reduce crosstalk interference between wire pairs. VAC Volts AC (alternating current, as opposed to DC - direct current). VACM (View‐Based Access Control Model) a new security feature defined by SNMPv3. Like User‐based Security Model (USM) it authenticates, encrypts, and decrypts SNMPv3 packets, as specified in RFC 2575. An SNMP entity's Access Control subsystem checks if a specific type of access to a specific managed object is allowed. Access control occurs in the agent when processing SNMP retrieval or modification request messages from a manager, and when a notification message is sent to the manager. VACM concepts are based the problems with SNMPv1 and SNMPv2c community strings. A community string identifies the requesting entity, the location of the requesting entity, and determines access control information and MIB view information. A single community string variable provides low flexibility and functionality. VACM builds on the community string concept with a stricter, and more dynamic, more easily administered access control model. Contrast with "USM". Valid address In IPv6, a preferred or deprecated address. A valid address may appear as the source or destination address of a packet, and the internet routing system is expected to deliver packets sent to a valid address to their intended recipients. Valid lifetime In IPv6, the length of time an address remains in the valid state (i.e., the time until invalidation). The valid lifetime must be greater than or equal to the preferred lifetime. When the valid lifetime expires, the address becomes invalid. Varbind In SNMP, a Sequence of two fields, an Object ID and the value for/from that Object ID. Varbinds is short for Variable bindings. It's the variable number of values that are included in an SNMP packet. Each varbind is made of an OID, type, and value. VCP (Virtual Com Port) A driver that allows a USB device to appear as an additional COM port. The USB device can be accessed by an application in the same manner as a regular COM port. VDC Volts DC (direct current, as opposed to AC - alternating current). VID (VLAN Identifier) The identification of the VLAN, which is defined by the standard IEEE 802.1Q. VID has 12 bits and allows the identification of 4096 VLANs. 33472 Rev. J https://www.transition.com Page 690 of 700