Our recent work on the regioselective synthesis of a number of heterocycles (4) prompted us to search for a simple and effi- cient reagent for this heterocyclization. We have recently achieved a facile entry to this ring system 6 (5) with the use of a well-known brominating agent, pyridine hydrobromide per- bromide, which we report here.
Voice VLAN. 1  Voice VLAN allows you to enhance VoIP service by configuring ports to carry IP voice traffic from IP phones on a specific VLAN. VoIP traffic has a preconfigured OUI prefix in the source MAC address. 2  You can configure VLANs on which voice IP traffic is forwarded.
As I said, a VLAN is a virtual LAN. In technical terms, a VLAN is a broadcast domain created by switches. Normally, it is a router creating that broadcast domain. With VLANâs, a switch can create the broadcast domain.This works by, you, the administrator, putting some switch ports in a VLAN other than 1, the default VLAN.All ports in a single VLAN are in a single broadcast domain. All devices, by default, are in VLAN 1. 2  A trunk port is a special port that runs ISL or 802.1q so that it can carry traffic from more than one VLAN. 3  For devices in different VLANâs to communicate, you must use a router or Layer 3 switch.