1 Report Overview 1.1 Study Scope 1.2 Market Analysis by Type 1.2.1 Global Unified Communications as a Service Market Size Growth Rate by Type: 2016 VS 2021 VS 2027 1.2.2 Cloud-Based 1.2.3 On-Premises 1.3 Market by Application 1.3.1 Global Unified Communications as a Service Market Share by Application: 2016 VS 2021 VS 2027 1.3.2 Medium-Sized Enterprise (499-1000 Users) 1.3.3 Small Enterprises (1-499Users) 1.4 Study Objectives 1.5 Years Considered 2 Global Growth Trends 2.1 Global Unified Communications as a Service Market Perspective (2016-2027) 2.2 Unified Communications as a Service Growth Trends by Regions 2.2.1 Unified Communications as a Service Market Size by Regions: 2016 VS 2021 VS 2027 2.2.2 Unified Communications as a Service Historic Market Share by Regions (2016-2021) 2.2.3 Unified Communications as a Service Forecasted Market Size by Regions (2022-2027) 2.3 Unified Communications as a Service Industry Dynamic 2.3.1 Unified Communications as a Service Market Trends 2.3.2 Unified Communications as a Service Market Drivers 2.3.3 Unified Communications as a Service Market Challenges 2.3.4 Unified Communications as a Service Market Restraints 3 Competition Landscape by Key Players 3.1 Global Top Unified Communications as a Service Players by Revenue 3.1.1 Global Top Unified Communications as a Service Players by Revenue (2016-2021) 3.1.2 Global Unified Communications as a Service Revenue Market Share by Players (2016-2021) 3.2 Global Unified Communications as a Service Market Share by Company Type (Tier 1, Tier 2 and Tier 3) 3.3 Players Covered: Ranking by Unified Communications as a Service Revenue 3.4 Global Unified Communications as a Service Market Concentration Ratio 3.4.1 Global Unified Communications as a Service Market Concentration Ratio (CR5 and HHI) 3.4.2 Global Top 10 and Top 5 Companies by Unified Communications as a Service Revenue in 2020 3.5 Unified Communications as a Service Key Players Head office and Area Served 3.6 Key Players Unified Communications as a Service Product Solution and Service 3.7 Date of Enter into Unified Communications as a Service Market 3.8 Mergers & Acquisitions, Expansion Plans 4 Unified Communications as a Service Breakdown Data by Type 4.1 Global Unified Communications as a Service Historic Market Size by Type (2016-2021) 4.2 Global Unified Communications as a Service Forecasted Market Size by Type (2022-2027) 5 Unified Communications as a Service Breakdown Data by Application 5.1 Global Unified Communications as a Service Historic Market Size by Application (2016-2021) 5.2 Global Unified Communications as a Service Forecasted Market Size by Application (2022-2027) 6 North America 6.1 North America Unified Communications as a Service Market Size (2016-2027) 6.2 North America Unified Communications as a Service Market Size by Type 6.2.1 North America Unified Communications as a Service Market Size by Type (2016-2021) 6.2.2 North America Unified Communications as a Service Market Size by Type (2022-2027) 6.2.3 North America Unified Communications as a Service Market Size by Type (2016-2027) 6.3 North America Unified Communications as a Service Market Size by Application 6.3.1 North America Unified Communications as a Service Market Size by Application (2016-2021) 6.3.2 North America Unified Communications as a Service Market Size by Application (2022-2027) 6.3.3 North America Unified Communications as a Service Market Size by Application (2016-2027) 6.4 North America Unified Communications as a Service Market Size by Country 6.4.1 North America Unified Communications as a Service Market Size by Country (2016-2021) 6.4.2 North America Unified Communications as a Service Market Size by Country (2022-2027) 6.4.3 United States 6.4.4 Canada 7 Europe 7.1 Europe Unified Communications as a Service Market Size (2016-2027) 7.2 Europe Unified Communications as a Service Market Size by Type 7.2.1 Europe Unified Communications as a Service Market Size by Type (2016-2021) 7.2.2 Europe Unified Communications as a Service Market Size by Type (2022-2027) 7.2.3 Europe Unified Communications as a Service Market Size by Type (2016-2027) 7.3 Europe Unified Communications as a Service Market Size by Application 7.3.1 Europe Unified Communications as a Service Market Size by Application (2016-2021) 7.3.2 Europe Unified Communications as a Service Market Size by Application (2022-2027) 7.3.3 Europe Unified Communications as a Service Market Size by Application (2016-2027) 7.4 Europe Unified Communications as a Service Market Size by Country 7.4.1 Europe Unified Communications as a Service Market Size by Country (2016-2021) 7.4.2 Europe Unified Communications as a Service Market Size by Country (2022-2027) 7.4.3 Germany 7.4.4 France 7.4.5 U.K. 7.4.6 Italy 7.4.7 Russia 7.4.8 Nordic 8 Asia-Pacific 8.1 Asia-Pacific Unified Communications as a Service Market Size (2016-2027) 8.2 Asia-Pacific Unified Communications as a Service Market Size by Type 8.2.1 Asia-Pacific Unified Communications as a Service Market Size by Type (2016-2021) 8.2.2 Asia-Pacific Unified Communications as a Service Market Size by Type (2022-2027) 8.2.3 Asia-Pacific Unified Communications as a Service Market Size by Type (2016-2027) 8.3 Asia-Pacific Unified Communications as a Service Market Size by Application 8.3.1 Asia-Pacific Unified Communications as a Service Market Size by Application (2016-2021) 8.3.2 Asia-Pacific Unified Communications as a Service Market Size by Application (2022-2027) 8.3.3 Asia-Pacific Unified Communications as a Service Market Size by Application (2016-2027) 8.4 Asia-Pacific Unified Communications as a Service Market Size by Region 8.4.1 Asia-Pacific Unified Communications as a Service Market Size by Region (2016-2021) 8.4.2 Asia-Pacific Unified Communications as a Service Market Size by Region (2022-2027) 8.4.3 China 8.4.4 Japan 8.4.5 South Korea 8.4.6 Southeast Asia 8.4.7 India 8.4.8 Australia 9 Latin America 9.1 Latin America Unified Communications as a Service Market Size (2016-2027) 9.2 Latin America Unified Communications as a Service Market Size by Type 9.2.1 Latin America Unified Communications as a Service Market Size by Type (2016-2021) 9.2.2 Latin America Unified Communications as a Service Market Size by Type (2022-2027) 9.2.3 Latin America Unified Communications as a Service Market Size by Type (2016-2027) 9.3 Latin America Unified Communications as a Service Market Size by Application 9.3.1 Latin America Unified Communications as a Service Market Size by Application (2016-2021) 9.3.2 Latin America Unified Communications as a Service Market Size by Application (2022-2027) 9.3.3 Latin America Unified Communications as a Service Market Size by Application (2016-2027) 9.4 Latin America Unified Communications as a Service Market Size by Country 9.4.1 Latin America Unified Communications as a Service Market Size by Country (2016-2021) 9.4.2 Latin America Unified Communications as a Service Market Size by Country (2022-2027) 9.4.3 Mexico 9.4.4 Brazil 10 Middle East & Africa 10.1 Middle East & Africa Unified Communications as a Service Market Size (2016-2027) 10.2 Middle East & Africa Unified Communications as a Service Market Size by Type 10.2.1 Middle East & Africa Unified Communications as a Service Market Size by Type (2016-2021) 10.2.2 Middle East & Africa Unified Communications as a Service Market Size by Type (2022-2027) 10.2.3 Middle East & Africa Unified Communications as a Service Market Size by Type (2016-2027) 10.3 Middle East & Africa Unified Communications as a Service Market Size by Application 10.3.1 Middle East & Africa Unified Communications as a Service Market Size by Application (2016-2021) 10.3.2 Middle East & Africa Unified Communications as a Service Market Size by Application (2022-2027) 10.3.3 Middle East & Africa Unified Communications as a Service Market Size by Application (2016-2027) 10.4 Middle East & Africa Unified Communications as a Service Market Size by Country 10.4.1 Middle East & Africa Unified Communications as a Service Market Size by Country (2016-2021) 10.4.2 Middle East & Africa Unified Communications as a Service Market Size by Country (2022-2027) 10.4.3 Turkey 10.4.4 Saudi Arabia 10.4.5 UAE 11 Key Players Profiles 11.1 Vonage 11.1.1 Vonage Company Details 11.1.2 Vonage Business Overview 11.1.3 Vonage Unified Communications as a Service Introduction 11.1.4 Vonage Revenue in Unified Communications as a Service Business (2016-2021) 11.1.5 Vonage Recent Development 11.2 LogMeIn 11.2.1 LogMeIn Company Details 11.2.2 LogMeIn Business Overview 11.2.3 LogMeIn Unified Communications as a Service Introduction 11.2.4 LogMeIn Revenue in Unified Communications as a Service Business (2016-2021) 11.2.5 LogMeIn Recent Development 11.3 CenturyLink 11.3.1 CenturyLink Company Details 11.3.2 CenturyLink Business Overview 11.3.3 CenturyLink Unified Communications as a Service Introduction 11.3.4 CenturyLink Revenue in Unified Communications as a Service Business (2016-2021) 11.3.5 CenturyLink Recent Development 11.4 Evolve IP 11.4.1 Evolve IP Company Details 11.4.2 Evolve IP Business Overview 11.4.3 Evolve IP Unified Communications as a Service Introduction 11.4.4 Evolve IP Revenue in Unified Communications as a Service Business (2016-2021) 11.4.5 Evolve IP Recent Development 11.5 Windstream 11.5.1 Windstream Company Details 11.5.2 Windstream Business Overview 11.5.3 Windstream Unified Communications as a Service Introduction 11.5.4 Windstream Revenue in Unified Communications as a Service Business (2016-2021) 11.5.5 Windstream Recent Development 11.6 Bell Canada 11.6.1 Bell Canada Company Details 11.6.2 Bell Canada Business Overview 11.6.3 Bell Canada Unified Communications as a Service Introduction 11.6.4 Bell Canada Revenue in Unified Communications as a Service Business (2016-2021) 11.6.5 Bell Canada Recent Development 11.7 Intermedia 11.7.1 Intermedia Company Details 11.7.2 Intermedia Business Overview 11.7.3 Intermedia Unified Communications as a Service Introduction 11.7.4 Intermedia Revenue in Unified Communications as a Service Business (2016-2021) 11.7.5 Intermedia Recent Development 11.8 PanTerra 11.8.1 PanTerra Company Details 11.8.2 PanTerra Business Overview 11.8.3 PanTerra Unified Communications as a Service Introduction 11.8.4 PanTerra Revenue in Unified Communications as a Service Business (2016-2021) 11.8.5 PanTerra Recent Development 12 Analyst's Viewpoints/Conclusions 13 Appendix 13.1 Research Methodology 13.1.1 Methodology/Research Approach 13.1.2 Data Source 13.2 Disclaimer 13.3 Author Details

List of Tables Table 1. Global Unified Communications as a Service Market Size Growth Rate by Type (US$ Million):2016 VS 2021 VS 2027 Table 2. Key Players of Cloud-Based Table 3. Key Players of On-Premises Table 4. Global Unified Communications as a Service Market Size Growth by Application (US$ Million): 2016 VS 2021 VS 2027 Table 5. Global Unified Communications as a Service Market Size by Regions (US$ Million): 2016 VS 2021 VS 2027 Table 6. Global Unified Communications as a Service Market Size by Regions (2016-2021) & (US$ Million) Table 7. Global Unified Communications as a Service Market Share by Regions (2016-2021) Table 8. Global Unified Communications as a Service Forecasted Market Size by Regions (2022-2027) & (US$ Million) Table 9. Global Unified Communications as a Service Market Share by Regions (2022-2027) Table 10. Unified Communications as a Service Market Trends Table 11. Unified Communications as a Service Market Drivers Table 12. Unified Communications as a Service Market Challenges Table 13. Unified Communications as a Service Market Restraints Table 14. Global Unified Communications as a Service Revenue by Players (2016-2021) & (US$ Million) Table 15. Global Unified Communications as a Service Market Share by Players (2016-2021) Table 16. Global Top Unified Communications as a Service Players by Company Type (Tier 1, Tier 2 and Tier 3) (based on the Revenue in Unified Communications as a Service as of 2020) Table 17. Ranking of Global Top Unified Communications as a Service Companies by Revenue (US$ Million) in 2020 Table 18. Global 5 Largest Players Market Share by Unified Communications as a Service Revenue (CR5 and HHI) & (2016-2021) Table 19. Key Players Headquarters and Area Served Table 20. Key Players Unified Communications as a Service Product Solution and Service Table 21. Date of Enter into Unified Communications as a Service Market Table 22. Mergers & Acquisitions, Expansion Plans Table 23. Global Unified Communications as a Service Market Size by Type (2016-2021) (US$ Million) Table 24. Global Unified Communications as a Service Revenue Market Share by Type (2016-2021) Table 25. Global Unified Communications as a Service Forecasted Market Size by Type (2022-2027) (US$ Million) Table 26. Global Unified Communications as a Service Revenue Market Share by Type (2022-2027) & (US$ Million) Table 27. Global Unified Communications as a Service Market Size Share by Application (2016-2021) & (US$ Million) Table 28. Global Unified Communications as a Service Revenue Market Share by Application (2016-2021) Table 29. Global Unified Communications as a Service Forecasted Market Size by Application (2022-2027) (US$ Million) Table 30. Global Unified Communications as a Service Revenue Market Share by Application (2022-2027) & (US$ Million) Table 31. North America Unified Communications as a Service Market Size by Type (2016-2021) (US$ Million) Table 32. North America Unified Communications as a Service Market Size by Type (2022-2027) & (US$ Million) Table 33. North America Unified Communications as a Service Market Size by Application (2016-2021) (US$ Million) Table 34. North America Unified Communications as a Service Market Size by Application (2022-2027) & (US$ Million) Table 35. North America Unified Communications as a Service Market Size by Country (2016-2021) & (US$ Million) Table 36. North America Unified Communications as a Service Market Size by Country (2022-2027) & (US$ Million) Table 37. Europe Unified Communications as a Service Market Size by Type (2016-2021) (US$ Million) Table 38. Europe Unified Communications as a Service Market Size by Type (2022-2027) & (US$ Million) Table 39. Europe Unified Communications as a Service Market Size by Application (2016-2021) (US$ Million) Table 40. Europe Unified Communications as a Service Market Size by Application (2022-2027) & (US$ Million) Table 41. Europe Unified Communications as a Service Market Size by Country (2016-2021) & (US$ Million) Table 42. Europe Unified Communications as a Service Market Size by Country (2022-2027) & (US$ Million) Table 43. Asia-Pacific Unified Communications as a Service Market Size by Type (2016-2021) (US$ Million) Table 44. Asia-Pacific Unified Communications as a Service Market Size by Type (2022-2027) & (US$ Million) Table 45. Asia-Pacific Unified Communications as a Service Market Size by Application (2016-2021) (US$ Million) Table 46. Asia-Pacific Unified Communications as a Service Market Size by Application (2022-2027) & (US$ Million) Table 47. Asia-Pacific Unified Communications as a Service Market Size by Region (2016-2021) & (US$ Million) Table 48. Asia-Pacific Unified Communications as a Service Market Size by Region (2022-2027) & (US$ Million) Table 49. Latin America Unified Communications as a Service Market Size by Type (2016-2021) (US$ Million) Table 50. Latin America Unified Communications as a Service Market Size by Type (2022-2027) & (US$ Million) Table 51. Latin America Unified Communications as a Service Market Size by Application (2016-2021) (US$ Million) Table 52. Latin America Unified Communications as a Service Market Size by Application (2022-2027) & (US$ Million) Table 53. Latin America Unified Communications as a Service Market Size by Country (2016-2021) & (US$ Million) Table 54. Latin America Unified Communications as a Service Market Size by Country (2022-2027) & (US$ Million) Table 55. Middle East & Africa Unified Communications as a Service Market Size by Type (2016-2021) (US$ Million) Table 56. Middle East & Africa Unified Communications as a Service Market Size by Type (2022-2027) & (US$ Million) Table 57. Middle East & Africa Unified Communications as a Service Market Size by Application (2016-2021) (US$ Million) Table 58. Middle East & Africa Unified Communications as a Service Market Size by Application (2022-2027) & (US$ Million) Table 59. Middle East & Africa Unified Communications as a Service Market Size by Country (2016-2021) & (US$ Million) Table 60. Middle East & Africa Unified Communications as a Service Market Size by Country (2022-2027) & (US$ Million) Table 61. Vonage Company Details Table 62. Vonage Business Overview Table 63. Vonage Unified Communications as a Service Product Table 64. Vonage Revenue in Unified Communications as a Service Business (2016-2021) & (US$ Million) Table 65. Vonage Recent Development Table 66. LogMeIn Company Details Table 67. LogMeIn Business Overview Table 68. LogMeIn Unified Communications as a Service Product Table 69. LogMeIn Revenue in Unified Communications as a Service Business (2016-2021) & (US$ Million) Table 70. LogMeIn Recent Development Table 71. CenturyLink Company Details Table 72. CenturyLink Business Overview Table 73. CenturyLink Unified Communications as a Service Product Table 74. CenturyLink Revenue in Unified Communications as a Service Business (2016-2021) & (US$ Million) Table 75. CenturyLink Recent Development Table 76. Evolve IP Company Details Table 77. Evolve IP Business Overview Table 78. Evolve IP Unified Communications as a Service Product Table 79. Evolve IP Revenue in Unified Communications as a Service Business (2016-2021) & (US$ Million) Table 80. Evolve IP Recent Development Table 81. Windstream Company Details Table 82. Windstream Business Overview Table 83. Windstream Unified Communications as a Service Product Table 84. Windstream Revenue in Unified Communications as a Service Business (2016-2021) & (US$ Million) Table 85. Windstream Recent Development Table 86. Bell Canada Company Details Table 87. Bell Canada Business Overview Table 88. Bell Canada Unified Communications as a Service Product Table 89. Bell Canada Revenue in Unified Communications as a Service Business (2016-2021) & (US$ Million) Table 90. Bell Canada Recent Development Table 91. Intermedia Company Details Table 92. Intermedia Business Overview Table 93. Intermedia Unified Communications as a Service Product Table 94. Intermedia Revenue in Unified Communications as a Service Business (2016-2021) & (US$ Million) Table 95. Intermedia Recent Development Table 96. PanTerra Company Details Table 97. PanTerra Business Overview Table 98. PanTerra Revenue in Unified Communications as a Service Business (2016-2021) & (US$ Million) Table 99. PanTerra Recent Development Table 100. Research Programs/Design for This Report Table 101. Key Data Information from Secondary Sources Table 102. Key Data Information from Primary Sources List of Figures Figure 1. Global Unified Communications as a Service Market Share by Type: 2020 VS 2027 Figure 2. Cloud-Based Features Figure 3. On-Premises Features Figure 4. Global Unified Communications as a Service Market Share by Application: 2020 VS 2027 Figure 5. Medium-Sized Enterprise (499-1000 Users) Case Studies Figure 6. Small Enterprises (1-499Users) Case Studies Figure 7. Unified Communications as a Service Report Years Considered Figure 8. Global Unified Communications as a Service Market Size (US$ Million), Year-over-Year: 2016-2027 Figure 9. Global Unified Communications as a Service Market Size (US$ Million), 2016 VS 2021 VS 2027 Figure 10. Global Unified Communications as a Service Market Share by Regions: 2020 VS 2027 Figure 11. Global Unified Communications as a Service Market Share by Regions (2022-2027) Figure 12. Global Unified Communications as a Service Market Share by Players in 2020 Figure 13. Global Top Unified Communications as a Service Players by Company Type (Tier 1, Tier 2 and Tier 3) (based on the Revenue in Unified Communications as a Service as of 2020 Figure 14. The Top 10 and 5 Players Market Share by Unified Communications as a Service Revenue in 2020 Figure 15. Global Unified Communications as a Service Revenue Market Share by Type (2016-2021) Figure 16. Global Unified Communications as a Service Revenue Market Share by Type (2022-2027) Figure 17. North America Unified Communications as a Service Market Size YoY Growth (2016-2027) & (US$ Million) Figure 18. North America Unified Communications as a Service Market Share by Type (2016-2027) Figure 19. North America Unified Communications as a Service Market Share by Application (2016-2027) Figure 20. North America Unified Communications as a Service Market Share by Country (2016-2027) Figure 21. United States Unified Communications as a Service Market Size YoY Growth (2016-2027) & (US$ Million) Figure 22. Canada Unified Communications as a Service Market Size YoY Growth (2016-2027) & (US$ Million) Figure 23. Europe Unified Communications as a Service Market Size YoY Growth (2016-2027) & (US$ Million) Figure 24. Europe Unified Communications as a Service Market Share by Type (2016-2027) Figure 25. Europe Unified Communications as a Service Market Share by Application (2016-2027) Figure 26. Europe Unified Communications as a Service Market Share by Country (2016-2027) Figure 27. Germany Unified Communications as a Service Market Size YoY Growth (2016-2027) & (US$ Million) Figure 28. France Unified Communications as a Service Market Size YoY Growth (2016-2027) & (US$ Million) Figure 29. U.K. Unified Communications as a Service Market Size YoY Growth (2016-2027) & (US$ Million) Figure 30. Italy Unified Communications as a Service Market Size YoY Growth (2016-2027) & (US$ Million) Figure 31. Russia Unified Communications as a Service Market Size YoY Growth (2016-2027) & (US$ Million) Figure 32. Nordic Unified Communications as a Service Market Size YoY Growth (2016-2027) & (US$ Million) Figure 33. Asia-Pacific Unified Communications as a Service Market Size YoY Growth (2016-2027) & (US$ Million) Figure 34. Asia-Pacific Unified Communications as a Service Market Share by Type (2016-2027) Figure 35. Asia-Pacific Unified Communications as a Service Market Share by Application (2016-2027) Figure 36. Asia-Pacific Unified Communications as a Service Market Share by Region (2016-2027) Figure 37. China Unified Communications as a Service Market Size YoY Growth (2016-2027) & (US$ Million) Figure 38. Japan Unified Communications as a Service Market Size YoY Growth (2016-2027) & (US$ Million) Figure 39. South Korea Unified Communications as a Service Market Size YoY Growth (2016-2027) & (US$ Million) Figure 40. Southeast Asia Unified Communications as a Service Market Size YoY Growth (2016-2027) & (US$ Million) Figure 41. India Unified Communications as a Service Market Size YoY Growth (2016-2027) & (US$ Million) Figure 42. Australia Unified Communications as a Service Market Size YoY Growth (2016-2027) & (US$ Million) Figure 43. Latin America Unified Communications as a Service Market Size YoY Growth (2016-2027) & (US$ Million) Figure 44. Latin America Unified Communications as a Service Market Share by Type (2016-2027) Figure 45. Latin America Unified Communications as a Service Market Share by Application (2016-2027) Figure 46. Latin America Unified Communications as a Service Market Share by Country (2016-2027) Figure 47. Mexico Unified Communications as a Service Market Size YoY Growth (2016-2027) & (US$ Million) Figure 48. Brazil Unified Communications as a Service Market Size YoY Growth (2016-2027) & (US$ Million) Figure 49. Middle East & Africa Unified Communications as a Service Market Size YoY Growth (2016-2027) & (US$ Million) Figure 50. Middle East & Africa Unified Communications as a Service Market Share by Type (2016-2027) Figure 51. Middle East & Africa Unified Communications as a Service Market Share by Application (2016-2027) Figure 52. Middle East & Africa Unified Communications as a Service Market Share by Country (2016-2027) Figure 53. Turkey Unified Communications as a Service Market Size YoY Growth (2016-2027) & (US$ Million) Figure 54. Saudi Arabia Unified Communications as a Service Market Size YoY Growth (2016-2027) & (US$ Million) Figure 55. UAE Unified Communications as a Service Market Size YoY Growth (2016-2027) & (US$ Million) Figure 56. Vonage Revenue Growth Rate in Unified Communications as a Service Business (2016-2021) Figure 57. LogMeIn Revenue Growth Rate in Unified Communications as a Service Business (2016-2021) Figure 58. CenturyLink Revenue Growth Rate in Unified Communications as a Service Business (2016-2021) Figure 59. Evolve IP Revenue Growth Rate in Unified Communications as a Service Business (2016-2021) Figure 60. Windstream Revenue Growth Rate in Unified Communications as a Service Business (2016-2021) Figure 61. Bell Canada Revenue Growth Rate in Unified Communications as a Service Business (2016-2021) Figure 62. Intermedia Revenue Growth Rate in Unified Communications as a Service Business (2016-2021) Figure 63. PanTerra Revenue Growth Rate in Unified Communications as a Service Business (2016-2021) Figure 64. Bottom-up and Top-down Approaches for This Report Figure 65. Data Triangulation Figure 66. Key Executives Interviewed

Vonage LogMeIn CenturyLink Evolve IP Windstream Bell Canada Intermedia PanTerra