Cisco CCNA Study Guide - Router Alley

More documents

Recommendations

Info

CCNA Study Guide v2.62 – Aaron Balchunas 296 Frame-Relay Traffic Shaping (FRTS) Frame-Relay’s method of QoS is called traffic-shaping, which controls the amount of traffic sent out an interface, and dictates congestion control mechanisms. Frame-Relay Traffic-Shaping (FRTS) is used for two purposes: • Adhering to the Frame provider’s traffic rates. • Preventing an oversubscription of the line between hub and spoke routers. Several terms must be understood before configuring traffic-shaping: • Committed Information Rate (CIR) – the “average” traffic rate provided on a best-effort basis. By default, the CIR on a serial interface configured for traffic shaping is 56000 bits per second. • Available Rate (AR) – the maximum traffic rate, dictated either by the speed of the physical interface (using the clock rate command), or the restrictions of the Frame Provider. • Minimum CIR (MinCIR) – the minimum traffic rate the router will “throttle” down to if congestion occurs on the Frame-Relay network (i.e., a BECN is received). This is usually the provider’s guaranteed traffic rate. By default, the MinCIR is half that of the CIR. • Discard Eligible (DE) – a bit that is set for all traffic sent above the MinCIR. Essentially, traffic that is sent above the Frame Provider’s guaranteed rate can or will be dropped when congestion occurs. • Committed Burst (Bc) – the amount of bits sent during a specific interval, measured as Time Committed (Tc). Tc is measured in milliseconds (default is 125ms, or 8 intervals a second), and determines the number of intervals per second. The CIR is derived from the Bc and Tc using the following formula: CIR = Bc X 1000/Tc • Excess Burst (Be) – the amount of bits that can be sent exceeding the Bc (or CIR). Any bits sent at this rate will be marked as DE. * * * All original material copyright © 2013 by Aaron Balchunas (aaron@routeralley.com), unless otherwise noted. All other material copyright © of their respective owners. This material may be copied and used freely, but may not be altered or sold without the expressed written consent of the owner of the above copyright. Updated material may be found at http://www.routeralley.com.
CCNA Study Guide v2.62 – Aaron Balchunas 297 Configuring Frame-Relay (FRTS) To configure FRTS, a map-class must be created: Router(config)# map-class frame-relay MYCLASS Router(config-map-class)# frame-relay cir 64000 Router(config-map-class)# frame-relay bc 8000 Router(config-map-class)# frame-relay be 0 Router(config-map-class)# frame-relay mincir 32000 Router(config-map-class)# frame-relay adaptive-shaping becn A map-class was created for frame-relay called MYCLASS. The first three commands configure the CIR, Bc, and Be respectively. The final commands must be used in conjunction with each other. The adaptive-shaping feature has been specified, indicating that the router will throttle back to the mincir if a becn is received. The router does not throttle down to the mincir immediately, but rather will lower the rate by 25% until either the congestion stops, or the mincir is reached. A map-class applied to an interface affects all PVCs on that interface. Additionally, map classes can be applied to a specific PVC, providing more granular control of FRTS. To apply a map class to an interface: Router(config)# interface s0/0 Router(config-if)# encapsulation frame-relay Router(config-if)# frame-relay traffic-shaping Router(config-if)# frame-relay class MYCLASS To apply a map class to a specific PVC: Router(config)# interface s0/0 Router(config-if)# encapsulation frame-relay Router(config-if)# frame-relay traffic-shaping Router(config-if)# frame-relay interface-dlci 101 class MYCLASS Do not forget the frame-relay traffic-shaping command. Once this command is configured, all PVCs are configured with the default CIR of 56,000 bps. * * * All original material copyright © 2013 by Aaron Balchunas (aaron@routeralley.com), unless otherwise noted. All other material copyright © of their respective owners. This material may be copied and used freely, but may not be altered or sold without the expressed written consent of the owner of the above copyright. Updated material may be found at http://www.routeralley.com.
Page 1 and 2:
CCNA Study Guide v2.62 - Aaron Balc
Page 3 and 4:
Page 5 and 6:
Page 7 and 8:
Page 9 and 10:
Page 11 and 12:
Page 13 and 14:
Page 15 and 16:
Page 17 and 18:
Page 19 and 20:
Page 21 and 22:
Page 23 and 24:
Page 25 and 26:
Page 27 and 28:
Page 29 and 30:
Page 31 and 32:
Page 33 and 34:
Page 35 and 36:
Page 37 and 38:
Page 39 and 40:
Page 41 and 42:
Page 43 and 44:
Page 45 and 46:
Page 47 and 48:
Page 49 and 50:
Page 51 and 52:
Page 53 and 54:
Page 55 and 56:
Page 57 and 58:
Page 59 and 60:
Page 61 and 62:
Page 63 and 64:
Page 65 and 66:
Page 67 and 68:
Page 69 and 70:
Page 71 and 72:
Page 73 and 74:
Page 75:
Page 78 and 79:
Page 80 and 81:
Page 82 and 83:
Page 84 and 85:
Page 86 and 87:
Page 88 and 89:
Page 90 and 91:
Page 92 and 93:
Page 94 and 95:
Page 96 and 97:
Page 98 and 99:
Page 100 and 101:
Page 102 and 103:
Page 104 and 105:
Page 106 and 107:
Page 108 and 109:
Page 110 and 111:
Page 112 and 113:
Page 114 and 115:
Page 116 and 117:
Page 118 and 119:
Page 120 and 121:
Page 122 and 123:
Page 124 and 125:
Page 126 and 127:
Page 128 and 129:
Page 130 and 131:
Page 132 and 133:
Page 134 and 135:
Page 136 and 137:
Page 138 and 139:
Page 140 and 141:
Page 142 and 143:
Page 144 and 145:
Page 146 and 147:
Page 148 and 149:
Page 150 and 151:
Page 152 and 153:
Page 154 and 155:
Page 156 and 157:
Page 158 and 159:
Page 160 and 161:
Page 162 and 163:
Page 164 and 165:
Page 166 and 167:
Page 168 and 169:
Page 170 and 171:
Page 172 and 173:
Page 174 and 175:
Page 176 and 177:
Page 178 and 179:
Page 180 and 181:
Page 182 and 183:
Page 184 and 185:
Page 186 and 187:
Page 188 and 189:
Page 190 and 191:
Page 192 and 193:
Page 194 and 195:
Page 196 and 197:
Page 198 and 199:
Page 200 and 201:
Page 202 and 203:
Page 204 and 205:
Page 206 and 207:
Page 208 and 209:
Page 210 and 211:
Page 212 and 213:
Page 214 and 215:
Page 216 and 217:
Page 218 and 219:
Page 220 and 221:
Page 222 and 223:
Page 224 and 225:
Page 226 and 227:
Page 228 and 229:
Page 230 and 231:
Page 232 and 233:
Page 234 and 235:
Page 236 and 237:
Page 238 and 239:
Page 240 and 241:
Page 242 and 243:
Page 244 and 245:
Page 246 and 247: CCNA Study Guide v2.62 - Aaron Balc
Page 304: CCNA Study Guide v2.62 - Aaron Balc
show all

Cisco CCNA Study Guide - Router Alley

Create successful ePaper yourself

Delete template?

Save as template?