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.
My Cisco. Per-VLAN Spanning Tree (PVST) maintains a spanning tree instance for each VLAN configured in the network. It uses ISL Trunking and allows a VLAN trunk to be forwarding for some VLANs while blocking for other VLANs.ince PVST treats each VLAN as a separate network, it has the ability to load balance traffic (at layer-2) by forwarding some VLANs on one trunk and other Vlans on another trunk without causing a Spanning Tree loop. Per-VLAN Spanning Tree (PVST) maintains a spanning tree instance for each VLAN configured in the network.