Wi-Fi and LTE co-location, general performance trending addendum

Transcription

1 Wi-Fi and LTE co-location, general performance trending addendum Final report Version 1.0 Tuomas Aaltonen Veli-Pekka Ketonen 1

2 Table of content General Test setup Log of changes Ethernet performance trending General Wi-Fi performance trending 2.4 GHz 5 GHz Challenges Observations Conclusions Suggestions 2

3 General This is an extension to the final report of 2.3 GHz LTE Wi-Fi co-location tests at Victoria station. This report includes some general Wi-Fi performance trending graphs which were not directly in the scope of the co-location report Conclusions are presented at the end of the report 3

4 Test setup 4

5 Test setup A LTE test transmitter and Ruckus WLAN access point were co-located 7signal Sapphire Wi-Fi service assurance and performance optimization product was used to analyze performance variations during the times when LTE transmitter was on and off Two types of 7signal Wi-Fi sensors were used Three with beam steering and one smaller sensor Larger sensor has one stream n and smaller has dual stream n capability 7signal measurement engine (Carat) was cloud based. Sensors were connected to cloud server through Ethernet. All collected data was stored to cloud During active tests 7signal sensors measure against a test end point. This test end point was also in cloud server During the test period, Victoria station Wi-Fi access point were connected to internet through 16/1Mbit/s ADSL connection. Normally a faster multi-adsl line has been available, but due to failure of aggregating device, only one ADSL line was available 5

6 Elements of 7signal Sapphire

7 Diagram of test setup elements Eyes performance active and passive tests Active tests operate over the LAN and WLAN separately Passive tests capture radio packets and calculate metrics from them

8 AP and Eye locations 8

9 LTE test transmitter LTE test signal was 20 MHz wide QPSK & 16QAM modulated synthesized TDD LTE traffic pattern Test signal center frequency was 2380 MHz Radiated output power levels were varied during the test 30, 36, 49 dbm mean EIRP values were tested 9

10 Eye 3 and LTE BTS 10

11 Log of changes 11

12 Test log from week 1 12

13 Test log from week 2 13

14 Test log from week 3 14

15 Ethernet performance Sensor Ethernet port towards the cloud based test end point 15

16 Eye Ethernet tests, downlink TP (Against cloud test end point) ADSL line connecting all access points to internet is a remarkable bottleneck 16

17 Eye Ethernet tests, downlink TP (Against cloud test end point) ADSL line connecting all access points to internet is a remarkable bottleneck Wired network throughput towards the internet dropped regularly to kbit/s range during busy traffic 17

18 Results and conclusions Used 16/1 ADSL is not sufficient enough to provide well performing WLAN to Victoria station end users This bottleneck also impacts test results in this project. Results from active end-to-end tests are mostly not limited by Wi-Fi radio connection but by the internet connection speed This limitation caused project to focus more on radio metrics than end-to-end performance 18

19 SLA compliancy 19

20 2.4 GHz SLA, daily averages Performance does not meet the defined target level Note: this is frequency band average and as access points were added to monitoring, they skew the data As well, changes to test profile were made during the period, like TCP test file size was reduced on 10.9 and VOIP tests removed 20

21 5 GHz SLA, daily averages 5 GHz performance is slightly better than 2.4 but does not meet the quality targets Note: this is frequency band average and as access points were added to monitoring, they skew the data As well, changes to test profile were made during the period, like TCP test file size was reduced on 10.9 and VOIP tests removed 21

22 2.4 GHz trend lines Access point level data 22

23 Beacon availability 23

24 Radio attach success rate 24

25 TCP downlink throughput, day average 25

26 TCP downlink throughput, hour average 26

27 TCP uplink throughput, day average 27

28 TCP uplink throughput, hour average 28

29 Eye retries in uplink towards AP, day average 29

30 Eye retries in uplink towards AP, hour average 30

31 AP retries in downlink toward Eye, day average 31

32 AP retries in downlink toward Eye, hour average 32

33 Round trip time, day average 33

34 Round trip time, hour average 34

35 AP signal level 35

36 AP retries towards clients, day average (passive test) 36

37 AP retries towards clients, hour averages (passive test) 37

38 Client retries towards APs, day average (passive test) 38

39 Client retries towards Aps, hour average (passive test) 39

40 WLAN traffic air time utilization 40

41 Number of clients/ap, hour average 41

42 Channels used by AP 42

43 5 GHz trend lines Access point level data 43

44 Beacon availability 44

45 Radio attach success rate 45

46 TCP downlink throughput, day average 46

47 TCP downlink throughput, hour average 47

48 TCP uplink throughput, day average 48

49 TCP uplink throughput, hour average 49

50 Eye retries toward access point, day average 50

51 Eye retries towards access point, hour average 51

52 Access point retries towards Eye, day average 52

53 Access point retries towards Eye, hour average 53

54 Round trip time, day average 54

55 Round trip time, hour average 55

56 AP signal level 56

57 Channels used by APs 57

58 Access point retries towards clients, day average 58

59 Access point retries towards clients, hour average 59

60 Client retries towards access point, day average 60

61 Client retries towards access point, hour average 61

62 WLAN traffic airtime utilization 62

63 Number of clients/access point, hour average 63

64 Data rates/mcss 64

65 Eye data rates in active TCP test 65

66 2.4GHs client data rates, download/upload (passive test) 66

67 5G Client data rates, download/upload (passive test) 67

68 Client devices 68

69 Client vendors, 2.4 GHz 69

70 Client vendors, 5 GHz 70

71 Radio environment 71

72 Channel usage, all BSSIDs in the area during the test period 72

73 Channel usage, all BSSIDs in the area during the test period 73

74 Summary 74

75 Observations 1/2 Overall Wi-Fi performance and service quality is modest. Clients experience connection to Wi-Fi but do not get sufficient throughputs for quality web browsing or other general data usage 2.4 GHz access points have users and 5 GHz radios users in peak hours Apple devices are dominating both bands (75%) Uplink throughput is very low, in the range of 100kbit/s. Downlink is also low, below 1Mbit/ s during day time 5 GHz radio works better than 2.4 GHz, as expected. However, the ADSL connection bottleneck limits better user experience there too The main limitation is the slow ADSL connection from Victoria station to internet Attach and beacon availability metrics are not accurate. During the measurements, band steering caused 2.4 GHz attach success rate to degrade. Band steering feature on purpose delays attach process for clients using 2.4 GHz which have been earlier seen using 5 GHz. Current 7signal band steering bypass feature is not optimal for Ruckus. Ruckus APs require 8 authorization requests to bypass and access it. 7signal sensors do not currently make these requests fast enough during each test and access to 2.4 GHz radio is delayed and may fail A lots of personal hotspots in the area 75

76 Observations 2/2 Active tests have relatively well balanced rate distribution Passively measured end user traffic data rates are spread across all the rates and include also the lowest rates down to 1 Mbit/s. This indicates that coverage may not be optimal Wi-Fi service Air utilization is high, also surprisingly high at 5 GHz band in the channels used by measured APs All (overlapping) 2.4 GHz channels are used. This causes packet loss and increases retries further Retry levels are very high. This indicates that used data rates are still too high in the given conditions. Rate control should reduce rates further if retries are in this high level. However, this is not uncommon behavior in Wi-Fi but increases rapidly air utilization and reduces overall network capacity APs make a lot of channels changes when trying to find better spectrum to operate There is significant amount of non-wi-fi interference in certain areas (Eye 1). This degrades Wi-Fi near to it 76

77 Recommendations Significantly faster ADSL/interconnection is needed to improve performance. This will have a significant positive impact to end users RF operation should be improved as well 2.4 GHz utilization is high during busy hours b should be disabled or at least the 1-2Mbit/s would need to be removed Less dense beaconing might be helpful (100ms -> 300ms). Optimally also other WLANS should follow this Radio link does not operate properly, uses too high data rates and has very high retry levels Organize and balance channel usage in the area (if possible) Disable the largest MCSs and data rates. Forces clients using lower rates Using A-MPDU aggregation might help lowering retries Review if coverage area is really sufficient with the current APs placements Source of interference near to Eye 1 should be located and removed if possible Better performance in the available Wi-Fi might reduce use of personal hotspot, which further would help improving the Wi-Fi performance Network performance can be improved significantly with optimization 77