## Line Graphs: Throughput and Packet Delay vs. Simulation Time ### Overview The image contains two line graphs plotted above each other, sharing a common x-axis representing simulation time. The top graph displays throughput (in 10^6 bits/sec) versus simulation time (in seconds), while the bottom graph shows packet delay (in seconds) versus simulation time (in seconds). Several routing protocols are compared across both graphs, with a legend provided to distinguish them. ### Components/Axes **Top Graph (Throughput):** * **Y-axis Title:** Throughput (10^6 bit/sec) * **Y-axis Scale:** 15.0 to 55.0, with increments of 10.0 * **X-axis:** Shared with the bottom graph (Simulation Time (sec)) **Bottom Graph (Packet Delay):** * **Y-axis Title:** Packet Delay (sec) * **Y-axis Scale:** 0.0 to 0.8, with increments of 0.2 * **X-axis Title:** Simulation Time (sec) * **X-axis Scale:** 200 to 1000, with increments of 100 **Legend (Located on the right side of the bottom graph):** * OSPF (Dashed line) * SPF (Solid line) * BF (Dotted-dashed line) * Q-R (Dotted line) * PQ-R (Dashed-double dotted line) * AntNet (Light solid line) * Daemon (Dashed line with larger dashes) ### Detailed Analysis **Top Graph (Throughput):** * **OSPF (Dashed line):** Starts at approximately 23 x 10^6 bit/sec, gradually increases to around 26 x 10^6 bit/sec by 400 seconds. It then sharply increases to approximately 38 x 10^6 bit/sec, plateaus until 500 seconds, and then drops back down to around 27 x 10^6 bit/sec, where it remains relatively stable. * **SPF (Solid line):** Starts at approximately 23 x 10^6 bit/sec, gradually increases to around 26 x 10^6 bit/sec by 400 seconds. It then sharply increases to approximately 45 x 10^6 bit/sec, plateaus until 500 seconds, and then drops back down to around 27 x 10^6 bit/sec, where it remains relatively stable. * **BF (Dotted-dashed line):** Starts at approximately 23 x 10^6 bit/sec, gradually increases to around 26 x 10^6 bit/sec by 400 seconds. It then sharply increases to approximately 47 x 10^6 bit/sec, plateaus until 500 seconds, and then drops back down to around 27 x 10^6 bit/sec, where it remains relatively stable. * **Q-R (Dotted line):** Starts at approximately 23 x 10^6 bit/sec, gradually increases to around 26 x 10^6 bit/sec by 400 seconds. It then sharply increases to approximately 47 x 10^6 bit/sec, plateaus until 500 seconds, and then drops back down to around 27 x 10^6 bit/sec, where it remains relatively stable. * **PQ-R (Dashed-double dotted line):** Starts at approximately 23 x 10^6 bit/sec, gradually increases to around 26 x 10^6 bit/sec by 400 seconds. It then sharply increases to approximately 46 x 10^6 bit/sec, plateaus until 500 seconds, and then drops back down to around 27 x 10^6 bit/sec, where it remains relatively stable. * **AntNet (Light solid line):** Starts at approximately 23 x 10^6 bit/sec, gradually increases to around 26 x 10^6 bit/sec by 400 seconds. It then sharply increases to approximately 45 x 10^6 bit/sec, plateaus until 500 seconds, and then drops back down to around 27 x 10^6 bit/sec, where it remains relatively stable. * **Daemon (Dashed line with larger dashes):** Starts at approximately 23 x 10^6 bit/sec, gradually increases to around 26 x 10^6 bit/sec by 400 seconds. It then sharply increases to approximately 40 x 10^6 bit/sec, plateaus until 500 seconds, and then drops back down to around 27 x 10^6 bit/sec, where it remains relatively stable. **Bottom Graph (Packet Delay):** * **OSPF (Dashed line):** Remains relatively stable at approximately 0.02 sec until 400 seconds, then sharply increases to approximately 0.8 sec, and returns to approximately 0.02 sec after 600 seconds. * **SPF (Solid line):** Remains relatively stable at approximately 0.02 sec until 400 seconds, then sharply increases to approximately 0.7 sec, and returns to approximately 0.02 sec after 600 seconds. * **BF (Dotted-dashed line):** Remains relatively stable at approximately 0.02 sec until 400 seconds, then increases with fluctuations to approximately 0.6 sec at 500 seconds, and returns to approximately 0.02 sec after 600 seconds. * **Q-R (Dotted line):** Remains relatively stable at approximately 0.02 sec until 400 seconds, then increases with fluctuations to approximately 0.5 sec at 500 seconds, and returns to approximately 0.02 sec after 600 seconds. * **PQ-R (Dashed-double dotted line):** Remains relatively stable at approximately 0.02 sec until 400 seconds, then increases with fluctuations to approximately 0.5 sec at 500 seconds, and returns to approximately 0.02 sec after 600 seconds. * **AntNet (Light solid line):** Remains relatively stable at approximately 0.02 sec until 400 seconds, then increases with fluctuations to approximately 0.5 sec at 500 seconds, and returns to approximately 0.02 sec after 600 seconds. * **Daemon (Dashed line with larger dashes):** Remains relatively stable at approximately 0.02 sec until 400 seconds, then sharply increases to approximately 0.8 sec, and returns to approximately 0.02 sec after 600 seconds. ### Key Observations * All protocols exhibit a significant increase in throughput between 400 and 500 seconds of simulation time. * Correspondingly, all protocols experience a spike in packet delay between 400 and 600 seconds. * The throughput values are very similar across all protocols, both before, during, and after the spike. * The packet delay values vary more significantly between protocols during the spike, with OSPF and Daemon showing the highest delay. ### Interpretation The graphs illustrate the performance of different routing protocols under a simulated network condition. The simultaneous increase in throughput and packet delay suggests a period of network congestion or a significant change in traffic patterns around the 400-second mark. The protocols appear to recover to their initial performance levels after approximately 600 seconds. The differences in packet delay during the congestion period may indicate varying levels of efficiency in handling the increased traffic load among the different protocols. The similarity in throughput suggests that all protocols are ultimately able to deliver the data, but the delay differences highlight potential trade-offs in latency.

\n ## Line Chart: Network Performance Comparison ### Overview The image presents two line charts displaying network performance metrics – Throughput and Packet Delay – over Simulation Time. The top chart shows Throughput in (10^6 bit/sec) and the bottom chart shows Packet Delay in (sec). Both charts compare the performance of several routing protocols: OSPF, SPF, BF, Q-R, PQ-R, AntNet, and Daemon. ### Components/Axes * **X-axis (Both Charts):** Simulation Time (sec), ranging from 200 to 1000 seconds. * **Y-axis (Top Chart):** Throughput (10^6 bit/sec), ranging from 15 to 55. * **Y-axis (Bottom Chart):** Packet Delay (sec), ranging from 0 to 0.8. * **Legend (Bottom-Right):** Lists the routing protocols being compared: * OSPF (Solid Black Line) * SPF (Solid Grey Line) * BF (Dashed Black Line) * Q-R (Dashed Grey Line) * PQ-R (Dotted Black Line) * AntNet (Dotted Grey Line) * Daemon (Dash-Dot Black Line) ### Detailed Analysis or Content Details **Top Chart - Throughput:** * **OSPF:** Starts at approximately 25 (10^6 bit/sec), remains relatively stable until around 400 seconds, then rapidly increases to approximately 48 (10^6 bit/sec). It then fluctuates between 45 and 48 (10^6 bit/sec) until around 550 seconds, after which it drops to approximately 25 (10^6 bit/sec) and remains stable. * **SPF:** Starts at approximately 25 (10^6 bit/sec), remains relatively stable until around 400 seconds, then rapidly increases to approximately 46 (10^6 bit/sec). It then fluctuates between 43 and 46 (10^6 bit/sec) until around 550 seconds, after which it drops to approximately 25 (10^6 bit/sec) and remains stable. * **BF:** Starts at approximately 25 (10^6 bit/sec) and remains relatively stable throughout the simulation, with minor fluctuations. * **Q-R:** Starts at approximately 25 (10^6 bit/sec) and remains relatively stable throughout the simulation, with minor fluctuations. * **PQ-R:** Starts at approximately 25 (10^6 bit/sec) and remains relatively stable throughout the simulation, with minor fluctuations. * **AntNet:** Starts at approximately 25 (10^6 bit/sec) and remains relatively stable throughout the simulation, with minor fluctuations. * **Daemon:** Starts at approximately 25 (10^6 bit/sec) and remains relatively stable throughout the simulation, with minor fluctuations. **Bottom Chart - Packet Delay:** * **OSPF:** Remains near 0 sec until approximately 400 seconds, then rapidly increases to approximately 0.6 sec, fluctuates significantly between 0.3 and 0.6 sec until approximately 600 seconds, and then drops back to near 0 sec. * **SPF:** Remains near 0 sec until approximately 400 seconds, then rapidly increases to approximately 0.5 sec, fluctuates significantly between 0.2 and 0.5 sec until approximately 600 seconds, and then drops back to near 0 sec. * **BF:** Remains near 0 sec throughout the simulation, with very minor fluctuations. * **Q-R:** Remains near 0 sec throughout the simulation, with very minor fluctuations. * **PQ-R:** Remains near 0 sec throughout the simulation, with very minor fluctuations. * **AntNet:** Remains near 0 sec throughout the simulation, with very minor fluctuations. * **Daemon:** Remains near 0 sec throughout the simulation, with very minor fluctuations. ### Key Observations * OSPF and SPF exhibit a significant increase in both throughput and packet delay around 400 seconds, followed by a return to initial levels around 550-600 seconds. This suggests a transient event or change in network conditions at that time. * BF, Q-R, PQ-R, AntNet, and Daemon maintain relatively stable performance throughout the simulation, with low packet delay and consistent throughput. * The throughput of OSPF and SPF is significantly higher than the other protocols during the peak period (400-550 seconds). * The packet delay for OSPF and SPF is significantly higher than the other protocols during the peak period (400-600 seconds). ### Interpretation The data suggests that OSPF and SPF protocols are more sensitive to changes in network conditions than the other protocols. While they can achieve higher throughput under certain circumstances, they also experience a significant increase in packet delay during those periods. This could indicate that OSPF and SPF are more prone to congestion or require more resources to adapt to changing network conditions. The stable performance of BF, Q-R, PQ-R, AntNet, and Daemon suggests that they are more robust and less susceptible to transient events. However, their throughput is consistently lower than that of OSPF and SPF during the peak period. The transient event around 400 seconds likely represents a change in network load or topology. The increase in throughput for OSPF and SPF suggests that they were able to adapt to the new conditions and utilize available bandwidth. However, the corresponding increase in packet delay indicates that this adaptation came at the cost of increased latency. The relationship between throughput and packet delay is a classic trade-off in network design. OSPF and SPF appear to prioritize throughput, while the other protocols prioritize low latency. The optimal choice of protocol depends on the specific requirements of the network.

## Dual-Axis Line Chart: Network Routing Algorithm Performance Comparison ### Overview The image displays a dual-axis line chart comparing the performance of seven network routing algorithms over a simulated time period. The chart is divided into two vertically stacked subplots sharing a common x-axis. The top subplot measures network throughput, while the bottom subplot measures packet delay. The simulation runs from 200 to 1000 seconds, with a notable event or change in network conditions occurring around the 400-second mark. ### Components/Axes * **Chart Type:** Dual-axis line chart (two subplots). * **Shared X-Axis:** * **Label:** `Simulation Time (sec)` * **Range:** 200 to 1000 seconds. * **Major Tick Marks:** At 200, 300, 400, 500, 600, 700, 800, 900, 1000. * **Top Subplot Y-Axis:** * **Label:** `Throughput (10^6 bit/sec)` (Megabits per second). * **Range:** 15.0 to 55.0. * **Major Tick Marks:** At 15.0, 25.0, 35.0, 45.0, 55.0. * **Bottom Subplot Y-Axis:** * **Label:** `Packet Delay (sec)`. * **Range:** 0.0 to 0.8 seconds. * **Major Tick Marks:** At 0.0, 0.2, 0.4, 0.6, 0.8. * **Legend:** * **Position:** Located in the bottom-right corner of the lower subplot. * **Content:** Lists seven algorithms with corresponding line styles. 1. `OSPF` - Dashed line (`---`) 2. `SPF` - Solid line (`—`) 3. `BF` - Dash-dot line (`-.-.`) 4. `Q-R` - Dotted line (`...`) 5. `PQ-R` - Dash-dot-dot line (`-..-..`) 6. `AntNet` - Densely dotted line (finer dots than Q-R) 7. `Daemon` - Long-dash line (`-- --`) ### Detailed Analysis #### Top Subplot: Throughput Analysis * **General Trend:** All algorithms show a similar pattern: a gradual increase from 200s to ~400s, a sharp spike and plateau between ~400s and ~520s, followed by a drop and stabilization from ~550s onward. * **Pre-Spike (200s - 400s):** Throughput for all algorithms rises steadily from approximately 20-22 Mbps to about 25-27 Mbps. * **Spike & Plateau (400s - 520s):** * A dramatic increase occurs at ~400s. * **OSPF & SPF:** Show the highest throughput, peaking near 50 Mbps and maintaining a plateau around 45-47 Mbps. * **BF, Q-R, PQ-R, AntNet, Daemon:** Plateau at a lower level, approximately 35-40 Mbps. The `BF` line appears slightly lower than the others in this group during the plateau. * **Post-Spike (520s - 1000s):** * Throughput drops sharply at ~520s. * All algorithms converge and stabilize at a nearly identical throughput of approximately 28-30 Mbps for the remainder of the simulation (600s to 1000s). The lines are tightly clustered, showing minimal difference. #### Bottom Subplot: Packet Delay Analysis * **General Trend:** Delay is very low and stable for all algorithms until ~400s. A significant disruption occurs between 400s and ~620s, after which delays return to near-zero levels. * **Pre-Disruption (200s - 400s):** Packet delay for all algorithms is negligible, hovering just above 0.0 seconds (likely < 0.05 sec). * **Disruption Period (400s - 620s):** * **OSPF & SPF:** Experience a moderate increase in delay, fluctuating between approximately 0.2 and 0.55 seconds. Their patterns are very similar. * **BF:** Shows the most severe degradation. Delay spikes to the maximum of 0.8 sec at ~420s, remains highly volatile between 0.4 and 0.8 sec until ~520s, then drops but remains elevated (~0.2-0.4 sec) until a final drop at ~620s. * **Q-R, PQ-R, AntNet, Daemon:** Exhibit a sharp, short-lived spike in delay to ~0.6-0.8 sec at ~400s, but quickly recover to lower levels (0.1-0.3 sec) by ~450s. They maintain this moderately elevated delay until ~520s, then drop back to near-zero. * **Post-Disruption (620s - 1000s):** All algorithms return to and maintain a very low packet delay, similar to the pre-disruption state (≈0.0 sec). ### Key Observations 1. **Correlated Event:** A major network event (e.g., link failure, traffic surge) at T=400s triggers a simultaneous response in both throughput and delay metrics. 2. **Performance Clustering:** Algorithms fall into distinct performance groups during the disruption: * **High-Throughput/Moderate-Delay:** OSPF, SPF. * **Lower-Throughput/Lower-Delay:** Q-R, PQ-R, AntNet, Daemon. * **Lower-Throughput/High-Delay:** BF (an outlier in delay performance). 3. **Convergence:** After the disruption ends (~T=600s), all algorithms converge to nearly identical performance in both throughput and delay, suggesting the network returns to a stable, possibly under-utilized state. 4. **BF Anomaly:** The `BF` algorithm demonstrates significantly worse and more persistent packet delay compared to all others during the disruption period, despite having throughput similar to the Q-R group. ### Interpretation This chart likely evaluates the resilience and adaptability of different routing algorithms under stress. The event at 400 seconds simulates a network disturbance. * **What the data suggests:** OSPF and SPF (likely traditional link-state algorithms) prioritize maintaining high data flow (throughput) during the event, at the cost of increased packet latency. Algorithms like Q-R, PQ-R, AntNet, and Daemon (possibly heuristic or adaptive algorithms) sacrifice some peak throughput to achieve lower and more stable delays. The `BF` (Bellman-Ford?) algorithm appears poorly suited for this scenario, suffering severe and prolonged latency issues. * **How elements relate:** The inverse relationship between throughput and delay during the disruption (400-520s) highlights a fundamental trade-off in network routing: maximizing data rate can lead to congestion and queuing delays. The post-600s convergence indicates that once the stressor is removed, the choice of routing algorithm becomes less critical for these metrics. * **Notable patterns/anomalies:** The near-perfect synchronization of the performance shift at 400s and recovery at 520s/600s across all algorithms is striking, indicating a controlled, scripted simulation event. The outlier behavior of `BF` is the most significant anomaly, suggesting it may have a slower convergence time or be more susceptible to routing loops under the tested conditions.

## Line Chart: Network Protocol Performance Metrics ### Overview The image contains two line graphs comparing the performance of various network routing protocols over simulation time. The top graph measures **Throughput (10⁶ bit/sec)**, while the bottom graph measures **Packet Delay (sec)**. The x-axis represents **Simulation Time (sec)** from 200 to 1000 seconds. Seven protocols are compared: OSPF, SPF, BF, Q-R, PQ-R, AntNet, and Daemon, each represented by distinct line styles. --- ### Components/Axes - **X-axis (Simulation Time)**: Labeled "Simulation Time (sec)" with ticks at 200, 300, 400, 500, 600, 700, 800, 900, and 1000 seconds. - **Y-axis (Top Graph)**: Labeled "Throughput (10⁶ bit/sec)" with values from 15.0 to 55.0. - **Y-axis (Bottom Graph)**: Labeled "Packet Delay (sec)" with values from 0.0 to 0.8. - **Legend**: Located on the right side of the chart, associating line styles with protocols: - **OSPF**: Dotted line - **SPF**: Solid line - **BF**: Dashed line - **Q-R**: Dotted line - **PQ-R**: Dotted line - **AntNet**: Dotted line - **Daemon**: Dotted line --- ### Detailed Analysis #### Top Graph (Throughput) - **OSPF (Dotted)**: Peaks at ~45.0 × 10⁶ bit/sec around 400s, then drops sharply to ~25.0 × 10⁶ bit/sec at 500s, stabilizing afterward. - **SPF (Solid)**: Shows a similar peak to OSPF but with a slightly smoother decline, maintaining ~25.0 × 10⁶ bit/sec after 500s. - **BF (Dashed)**: Remains flat at ~20.0 × 10⁶ bit/sec throughout the simulation. - **Q-R (Dotted)**: Peaks at ~30.0 × 10⁶ bit/sec at 400s, then drops to ~15.0 × 10⁶ bit/sec at 500s. - **PQ-R (Dotted)**: Similar to Q-R but with a less pronounced drop, stabilizing at ~20.0 × 10⁶ bit/sec. - **AntNet (Dotted)**: Flat at ~10.0 × 10⁶ bit/sec. - **Daemon (Dotted)**: Flat at ~5.0 × 10⁶ bit/sec. #### Bottom Graph (Packet Delay) - **OSPF (Dotted)**: Spikes to ~0.6 sec at 400s, then drops to ~0.2 sec at 500s, remaining stable. - **SPF (Solid)**: Similar spike to OSPF but with a slightly slower decline, stabilizing at ~0.3 sec. - **BF (Dashed)**: Flat at ~0.1 sec. - **Q-R (Dotted)**: Spikes to ~0.5 sec at 400s, drops to ~0.3 sec at 500s. - **PQ-R (Dotted)**: Similar to Q-R but with a slower decline, stabilizing at ~0.25 sec. - **AntNet (Dotted)**: Flat at ~0.05 sec. - **Daemon (Dotted)**: Flat at ~0.02 sec. --- ### Key Observations 1. **Performance Variance**: OSPF and SPF exhibit the highest throughput and lowest packet delay, suggesting superior performance. 2. **Spike and Drop**: All protocols show a sharp increase in packet delay and a drop in throughput at 400s, followed by a recovery at 500s. This may indicate a simulated network event (e.g., congestion or failure). 3. **Protocol Differences**: BF, AntNet, and Daemon maintain consistently low throughput and delay, while Q-R and PQ-R show intermediate performance. 4. **Line Style Consistency**: All dotted lines (OSPF, Q-R, PQ-R, AntNet, Daemon) align with their legend labels, confirming accurate data representation. --- ### Interpretation The data suggests that **OSPF and SPF** are the most efficient protocols in this simulation, balancing high throughput and low delay. The sharp spike in packet delay at 400s and subsequent drop at 500s likely reflects a transient network condition (e.g., a link failure or congestion event). Protocols like BF, AntNet, and Daemon perform poorly in terms of throughput but maintain minimal delay, possibly due to simpler routing mechanisms. The consistent use of line styles in the legend ensures clarity, though the absence of color limits visual distinction. This chart highlights the trade-offs between protocol complexity and performance under dynamic network conditions.