Applications for SmartNode 4520 Series 29Model 4520 & 4110 Series Getting Started Guide 2 • Applications OverviewApplications for SmartNode 4520 SeriesThese models have dual 10/100Base-T Ethernet ports. The second Ethernet port provides Ethernet and IPlayer QoS services. Voice prioritization and rate limitation to avoid network congestion and the respectivevoice quality degradation.Application—Desktop or LAN segment QoSThese models can be used by the network administrator to provide QoS tagging and management for individ-ual desktops or LAN segments.Figure 12. Desktop/Segment QoS Switch/GWApplication—Point-to-point WAN QoS SwitchThe 4520 Series router can be used by the network administrator to provide QoS tagging and managementpoint-to-point WAN links (see figure 12). The following data forwarding modes are supported:• Ethernet switching: applicable for wire-speed switching at 10 or 100 Mbps useful in LAN segmentation,LAN extension (VDSL, fiber) or fiber access. In this mode hardware 802.1p prioritization is available butno software based queuing or rate limiting features. 1• Bridging: useful for speeds less than 10 Mbps (DSL, leased-line bridges) where network administration androuting can be simplified by inserting a bridge instead of a router (e.g. in combination with VPN-Firewall).Software based QoS mechanisms such as rate limiting and queuing can be applied in this mode. 1• Routing: useful for speeds less than 10 Mbps where the SmartNode provides routing service such as NAT,ACL, DHCP, PPPoE etc. and the full software based QoS functionality of SmartWare.Note The layer 2 QoS switch cannot provide downstream QoS for networks con-nected to an IP WAN where various sources can congest the downstream.1. Availability depending on SmartWare release and configuration.